Method and device for measurement of component amount coming from gas atmosphere during thermochemical treatment of metal parts

FIELD: physics; measurement.

SUBSTANCE: invention is related to method, and also to device for measurement of component amount coming from surrounding gas atmosphere and received by parts in process of thermochemical treatment of metal parts. Sample, lengthwise size of which considerably exceeds its cross size, is exposed to gas atmosphere impact. Change of sample length in time in lengthwise direction is measured, being the result of component transfer from gas atmosphere, and measured change of length is used for determination of component amount that was transferred from gas atmosphere to sample. Method is performed isothermally or at changing temperature, at that change of length resulted from temperature change is compensated in calculations. In order to realise the method, device is used that incorporates clamp for sample used in method, system of length measurement for registration of sample length change in time in longitudinal direction, and also computing unit. Method provides possibility to obtain much more accurate data on amount of component coming from gas atmosphere and received by parts.

EFFECT: obtainment of much more accurate data on amount of component coming from gas atmosphere and received by parts.

14 cl, 11 dwg, 1 ex

 

The invention concerns a method and device for measuring coming from the surrounding gas atmosphere and take details of the number of the component during heat treatment of metal parts.

Thermochemical processes, such as carburizing, nitriding or carbonitriding, are of great importance, as they allow you to give the details in the surface area of special mechanical, physical and/or chemical properties. While many thermochemical processes carried out in the temperature effects through the selection of one or more components from the gas phase, as a consequence soluble atoms of the components, for example carbon or nitrogen into solution and form a connection with alloying components material components, such as carbides, nitrides or carbonitrides.

The desired properties depends primarily on the geometry and composition of the created surface layer, that is, the concentration profile, as well as the connections of the components in the surface region. When the concentration profile is the result of composition, temperature and duration of exposure on the part of the gas atmosphere and can be determined by an appropriate choice of the parameters of time, temperature, pressure, and composition of the gas is.

However, in many cases setting the above parameters cannot be so precisely that it can accurately predict thermochemical processing. A significant reason for this is that thermochemical processes occur in strongly nonequilibrium conditions, and their kinetics depends, including the state of the external surface exposed to the processing details. To this are added convective conditions in the reactor, and the presence of other reactive surfaces on which the processing gas in an uncontrolled manner reacts.

So based on the calculated at least partly eliminate the above-mentioned interfering factors, developed in particular by cementation, different measurement techniques and data processing, which, however, do not provide an accurate prediction of the flow method.

For example, when subjected to carburizing treatment details at temperatures in the range from 900 to 1100°exposed to a carbon-containing atmosphere. At the same time as the carbon source may be a hydrocarbon, such as methane or propane, at a temperature of processing disintegrate and release of hydrogen and carbon atoms are transferred to the metal surface. Due to physical and chemical absorption of carbon atoms is hatshepsuts and subsequently penetrate by diffusion into the metal, and raises the profile of concentration, which upon cooling forms a corresponding hardness profile. If along with the hydrocarbons still has the oxidant, for example carbonic acid and/or water vapor, which is a direct process of cementation due to carbon monoxide, which is formed in the reaction with the oxidant. Then by splitting the absorbed molecules of carbon monoxide on the surface of the workpiece is carried out by direct reaction of cementation, thus releasing the oxygen atom. The removal of oxygen from the surface is largely determined by the speed of the degradation process and together with the cementation of the surface layer. The above can be performed either by reaction of the absorbed molecules of carbon monoxide with another molecule of carbon monoxide to carbon dioxide, or by reaction with the hydrogen molecule with the formation of water vapor, the latter reaction proceeds very quickly. This newly formed water can again recover the newly announced hydrocarbon to carbon monoxide and hydrogen than the cycle of the reaction.

When knowledge of the composition of the alloy and temperature cementation through the measurement of partial pressures can be calculated equilibrium carbon content is. This carbon content is denoted as C-level. In the field of activity of carbon, corresponding to the cementation process, water is almost completely dissociates, that is, the relative content of the monoxide of carbon and hydrogen, can be considered permanent. Thus slight residual hydrogen content can be taken as a defining carbon activity, the hydrogen content can be accurately determined, for example, by the method of dew point.

In a similar cementitious system carbon monoxide/dioxide, which corresponds to the equilibrium condition of the system of CO2With WITH carbon dioxide in contrast to other gases present in very low levels, which is crucial for the activity of the carbon. The definition of minor amounts of carbon dioxide can be carried out by infrared spectroscopy method.

Another method for determining the activity of carbon is to use equilibrium with oxygen, as, for example, for determining the activity of the carbon ratio of hydrogen and water vapor turns out that it is at a certain temperature is in equilibrium with the partial pressure of oxygen. When the oxygen partial pressure can be set by measuring the solid electrolyte probe (ED is).

All of the above methods of measurement, which are trying to install carbonizing action of the atmosphere, assume that the atmosphere is in equilibrium with the surface subjected to the processing details. However, the effective concentration of carbon, which is actually mounted on a metal surface during the implementation process, depends on one hand on the speed of delivery of carbon from the atmosphere, and on the other side of the speed with which the carbon diffuses into the metal. A major factor is how quickly released during the process of dissolving carbon oxygen is removed from the surface. In addition, for a truly achievable carburizing matters is whether the removal of oxygen from the surface by reaction with carbon monoxide or hydrogen. In addition, it also plays an important role in convective conditions in the reactor.

Naturally, the dimension changes of the gas composition in the reactor is indirect and in many cases inadequate and even inaccurate description really happening on the surface of the material processes. While the process can be more complicated if in the heat treatment furnace by increasing the carbon activity results in the release of soot, or if a portion of the carbonizing gas uses the I, to restore the oxidized surface details.

Thus, previously known from the prior art methods of measurement and data processing is not suitable for you can make a fairly accurate prediction of stroke thermochemical process.

This implies that the object of the invention is to provide such a method of measurement, which during the machining process allows you to get much more accurate data about the quantity of gas atmosphere and take details of the component.

To solve this problem is proposed by the invention method for continuous measurement of the incoming thermochemical processing of metal parts of the surrounding gas atmosphere and take details of the number of the component in which the sample is, the longitudinal dimension of which substantially exceeds its transverse dimension, is exposed to the gas atmosphere; measure caused by the receipt from the gas atmosphere component change with time of the sample length in the longitudinal direction, and using the measured change in length to determine the number received from the gas atmosphere in the sample component.

Corresponding to the invention the method is based on the technical knowledge that the sample due to receipts from the gas atmosphere component is a, undergoes a volume change, which in the longitudinal direction of the sample is reflected in the changes in length, which can be directly registered and used to determine the number of received component. The change of volume occurs through the expansion of the crystal lattice of iron during the implementation of the component atoms and/or by the occurrence of secretions, which are formed component with one or more alloying elements of the sample material. Corresponding to the invention, the proposed method allows to directly measure passed from the gas atmosphere, the quantity of the component, in contrast to known prior art methods of measurement and data processing has the advantage that it is caused by pressure, temperature, reaction surface, and that such variations have no influence on the measurement result. Therefore, corresponding to the invention the method provides a precise definition passed in a sample of the gas atmosphere, and thus the workpiece, the number of the component. When determining the number can mainly be carried out continuously, which creates the opportunity for more accurate forecasting on the basis of the measurement processes in time, by calculation can on latisa forecasts, which due to the high accuracy of measurement relevant to the invention method have only a small probability of error.

To determine the length change of the specimen is inserted in generated for this clip. The clamp consists of two supports, one of the pillars accurately fixed in position, and the other bearing is that they can move relative to the fixed support. Due to the increase in length located between the two supports, one sample bearing moves relative to the other support. Due to the variation in length of the specimen full lateral movement of both of the supports relative to each other corresponds to occur a complete change in length of the specimen. The change in length of the specimen is due to the transition from gas atmosphere component, and the component diffuses into the sample perpendicular to its longitudinal axis. Along with this diffusion component is the change in volume of the sample, which both formed perpendicular to the longitudinal axis of the sample end surface also causes a change in the surface profile. First, both the end of the sample surface is made flat, so that the variation over time in the level of surface profile of both end surfaces of the sample as a whole leads to a change in the time length of the sample. Change savremeni level of surface profile and accordingly resulting from this change of the sample length used in accordance with the claimed method, to determine the quantity of the component entering the sample. When the measured change in length can be used as a directly measured value, which determines the quantity of the component, which was adopted by the sample.

According to the following characteristic of the invention, the sample and the parts exposed to the gas atmosphere at the same temperature. Thus, as for the sample, and parts have the same initial conditions, so that measured on the sample correlation can be transferred to the exposed processing details without corrective calculations. This occurs in particular when the sample and the details of the selected identical material. The sample may be placed directly in the furnace installation for thermochemical processing. The sample can be used as a sensor direct action or flow sensor carbon directly into the plant for thermochemical processing. An alternative can also be provided that the sample is outside the installation, and it is served selected from the atmosphere of the installation of the gas stream.

According to another characteristic of the invention provides that the holding method is isothermal. This process has the advantage that the sample varies the t length, and not susceptible to temperature changes. Determination of the quantity of received component then may be a simple way without corrective calculations. In addition, the alternative can also be provided that the method is carried out at varying temperature. This, in particular, is required if the implementation of the method of processing metal parts technologically cannot be carried out only at one temperature. The implementation of the method under varying temperature requires compensation by calculation resulting from temperature changes additional changes in length of the specimen. Although this represents an additional cost, relatively isothermal implementation of the method, but has the advantage that corresponding to the invention the method may also include such options in which during the implementation of the method are different temperatures.

According to another characteristic of the invention provides that the change in surface profile, resulting in a cooling of the sample, preferably the length change of the sample in the longitudinal direction, and/or the temperature range of this change, are used to determine the quantity and distribution of the rolling component. As is known, when the phase preframe the AI Fe-based materials, for example, if the transformation from austenite to pearlite, there are changes in the volume or change the length, size and temperature range are related to the number and distribution of pre-adopted from the gas atmosphere component. In contrast to known prior art methods of measurement and processing corresponding to the invention method allows to determine or predict not only the quantity but also the distribution transferred from the gas atmosphere part or component sample. In particular, when geometrically complex and expensive parts this is an advantage, as it can provide accurate prediction concerning the transition component of the gas atmosphere, for those areas of detail that is geometrically difficult to access. In addition, by using the appropriate the invention, a method may determine or predict the concentration profile.

According to another characteristic of the invention provides that massoperedacha the sample corresponds to that for details. This can be achieved thanks to the fact that the sample is placed directly in the furnace chamber near parts or, respectively, if it is placed outside the furnace, around the sample are similar conditions of load and temperature.

Another prize is the aka of the invention the gas stream, contains a component that runs at a certain speed near the sample and/or details. This variant of the method mainly helps the realization of more accurate measurements of the length change of the sample and however obtaining more accurate data on the number of promoted component.

According to another characteristic of the invention when using a tubular sample transition component is only the outer lateral surface. This can be achieved, for example, due to the fact that the inner side surface of the tubular sample closed or provided with an impervious component for the outer layer.

According to another characteristic of the invention provides that the movable component is carbon. In this case, the sample serves as a "probe" or "probe" and contributes to the determination of the amount of carbon that is in the process of carburizing is transmitted from the carrier of the carbon contained in the gas atmosphere, to the sample and also to nauglerozhivaniya details.

As a device for solving the above problem, a device for the continuous measurement of the entrants in the heat treatment of metal parts from the surrounding gas atmosphere and rolling in the part number of the component, including clip sample, a longitudinal dimension which is substantially revised its transverse dimension, system length measurement for registration of the change in time of the sample length in the longitudinal direction, and the processing unit.

The device offers a clip sample. The clamp is used to secure the sample in the gas atmosphere. This clip connected system for length measurement, which is used to record changes in the time length of the specimen in the clamp. This measured change in length of the specimen in the longitudinal direction. Measured by the system for measuring the length change of the sample length is served in a computing unit that, when used in certain steps of the calculation determines the measured length change amount transferred from the gas atmosphere in the sample component. Use of the invention device mainly allows you to define a number of component passed through directly measured geometric size, so using the proper invention device may very largely be eliminated by external factors, which are known from the prior art indirect methods of measurement and processing cause distortion of the measurement result. Thus, by using the appropriate invention device, you can obtain accurate measurement values, and to make accurate forecasts in respect of a transferring of the gas atmosphere in the sample or in the part number of the component.

According to the following characteristic of the invention provides that clip sample has two supports, and the position of one of the supports is fixed relative to the system for length measurement. Therefore, provided the first bearing located stationary relatively to the system for measuring length, and the second support, which is movable relatively to the first support and the system for measuring length. Placed in the clamp of the sample retained on the ends of both legs. Before the implementation of thermochemical process end of the sample surface is planar and adjacent to their corresponding supports. During the implementation of the method because of the transition component from the gas phase change of the sample volume, which also causes a change in the profile of end surfaces of the sample adjacent to both supports. The change in the surface profile is manifested in the variation over time in the level originally made flat end surfaces, so that due to the transfer of the component from the gas phase in the sample is the elongation of the sample in the longitudinal direction. This change in length in the longitudinal direction causes movement of support located relatively movable. This movement supports registered by the system length measurement and is passed to calculate the nutrient block, then on the basis of the specific rules for the calculation converts the reported change in length of the specimen to determine the number of switched component.

According to the following characteristic of the invention, at least one portion of the clip for the sample is located inside the gas atmosphere. This event ensures that the sample is largely exposed to the same gas atmosphere, and the workpiece. Therefore, preferably, provided that the entire clip together with the sample is located inside the gas atmosphere.

According to the following characteristic of the invention, the measuring system length is located outside of the gas atmosphere, or at least outside the heated zone of the gas atmosphere. This arrangement has the advantage that it is not affected by temperature and pressure occurring inside the gas atmosphere. Thus, mainly due to the external influence of the distortion of the measurement result can be excluded.

According to the following characteristic of the invention, the system for measuring the length of an optical system. Preferably applied using a laser measuring system length, which provides extremely accurate measurement results. An alternative can also be provided by the mechanical system and the intent length, which differs from the optical system of length measurement has the advantage that it is less sensitive to external influences.

According to another characteristic of the invention provides a flowing channel for the sample. As the ambient channel can be used, for example, the pipe, which is located inside the sample. The use of flowing channel has the advantage that it can be created in the specified environment, the ambient sample, which provides a more accurate measurement result.

According to another characteristic of the invention includes a temperature sensor. This sensor is used to determine changes in the implementation of the method, the temperature of the atmosphere that surrounds the details and a sample. Thus, caused by the temperature change in time length of the sample can be accounted for by temperature and transferred for the implementation of corrective calculation in connected computing unit. The determination of the number of rolling component is then calculated from the measured length change of the sample on the one hand, and certain of temperature an additional change in the length of the specimen from the other side.

In relation to the sample, the invention features a sample for maintaining yunogo measuring the amount of the component transitioning from the surrounding parts of the gas atmosphere, thermochemical processing of metal parts with a longitudinal dimension that is substantially greater than the transverse size.

Such geometrical run the sample has the advantage that the volume change caused by the passing of the gas atmosphere component, particularly in relation to the longitudinal elongation, resulting in a simplified, with the preferred implementation of the method. As a sample, it is preferable to use a cylindrical rod or made in the form of a pipe sample. To prevent the tubular sample the transition component of the gas atmosphere on the inside, this surface is provided with an impervious component for the covering layer.

Other advantages and distinctions of the invention follow from the drawings that show the following.

Figure 1 - graph of concentration profiles.

Figure 2 - graph of the profile length.

Figure 3 - assuming plastic character, chart, profile changes in the concentration at time t1.

Figure 4 - when the assumption of a plastic nature, chart, profile changes in the concentration at time t2.

Figure 5 - graph of the concentration profile of the first step of the method.

Figure 6 - diagra the mA changes of the concentration profile of the second step of the method.

Figure 7 - schematic representation corresponding to the invention the device according to the first variant implementation.

On Fig - schematic representation corresponding to the invention the device according to the second variant implementation.

Figure 9 - graph of the time variation of the length of the sample.

Figure 10 - diagram of the length changes of temperature.

Figure 11 - schematic representation corresponding to the invention the device according to the third variant of implementation.

Figure 1 is a waveform showing the change of the profile 16 of the concentration in the cross section of the sample perpendicular to the longitudinal direction of the sample. In this position 13 underlying spatial coordinate, and the position of the 14 - concentration. The point of intersection of the spatial coordinates 13 and 14 concentration indicated by the position 131 and corresponds with respect to spatial coordinates 13 the border, that is, the side surface of the sample.

As shows the change of the profile 16 of the concentration profile starts from the maximum concentration 16A and decreases with increasing spatial coordinates 13 to values 16C, which essentially corresponds to the initial concentration in the sample before carrying out a thermochemical process. Point 16b denotes the point of intersection of the curve of the profile 16 of the concentration and the medium is about values 16d profile 16 of the concentration with respect to the boundary concentration 16A and initial concentration 16C.

When performing thermochemical process for processing of metal parts, a component, such as carbon moves from the gas atmosphere in the metal part. However, the introduction of atoms in the internode metal lattice detail leads to expansion of the crystal lattice, which at the macroscopic level leads to an increase in volume. This increase is approximately proportional to the increase in the concentration of the component. On the sample, the longitudinal size of which is considerably greater than the transverse size of this increase can be seen as a linear elongation in the longitudinal direction. If this change in length compared with the original length, it makes a relative elongation of the sample as a function of the concentration changes.

Figure 2 assuming linear-elastic nature of the sample, the curve 161 shows the profile of the lengths of the sample along the spatial coordinates 13, which corresponds to the sample, the assumption that the individual layers are mechanically freely movable relative to each other. Due to the proportionality between the relative elongation on one side and the absorption component on the other hand it turns out the profile 161 length, which is proportional to the profile 162 concentration. At the boundary, i.e. on n the outer region of the lateral surface of the sample, sets the maximum relative length a, while inside the sample always remains the original length s. The dash-dotted straight 161d corresponds to the average value of the relative change of length.

Shown in figure 2, the change comes from the hypothetical assumption that the individual layers of the sample are mechanically freely movable relative to each other. However, in reality, the individual layers are connected to each other, i.e. they are not free to change the length in accordance with the local concentration of the passed component that causes the shear stress. Marked on the figure 2 position 161b place characterizes the neutral fiber, that is, the line pattern in which compressive stresses are more enriched in the boundary region are moving in the tensile stress of the inner region of the sample. Through the impact of these stresses are presented in figure 2 hypothetical profile relative changes 161 deformed length to the effective profile changes 162 length, i.e. the maximum elongation a under the influence of compressive stresses is reduced to values a elongation, while the minimum elongation s by tensile stresses increases to values 162d.

In relation to figure 3, 4 will be completely plastic is the first character. While figure 3 shows the concentration profile 16 at the time t1 and time profile 17 concentration at a later point in time t2. Position 16A denotes a constant surface concentration, and the position 16C corresponds to the initial value before the start of diffusion in volume that occurs inside the sample in both the specified time. Position 16b and 17b respectively show the place where you set the average concentration corresponding to the dotted lines 16d and 17d, in both time. Coordinate 132 corresponds to the maximum change a concentration between the two times t1 and t2.

The diagram in figure 4 shows local changes in the concentration of, respectively, the axis 141, between times t1 and t2 along the axis 13 of the spatial coordinates, i.e. in the direction of diffusion across the longitudinal direction of the sample. Thus the dotted line 17f corresponds to the increase in the average concentration between these points in time.

For the chart in figure 5, in which the axis 711 denotes the relative change of length, it is assumed that the original profile of the length of the sample at time t1 is flat, that is, in contrast to the example that is illustrated in the fully elastic case in figure 1 and 2, the profile is continuously aligned under the influence of shear stress during diffusion. If this is t the relaxation process between times t1 and t2 are "frozen" at some point, the profile length change would be appropriate curve 18 according to figure 5, and the value 132 coordinates corresponds to the maximum relative change 18E length, which leads to the formation of a zone of compressive stresses. At points 18g and 18h negative shear stress on both sides enters the zone of positive shear stress. Area compressive stresses, and both zones of tensile stress are represented by different shading.

Chart figure 6 shows a second thought the relaxation stage profile 18 length figure 5. Thus under the action of compressive stress field profile is omitted, while other areas are raised, and the final level is established over the entire surface and is determined by the corresponding average value 18h profile length.

In fact mentally separated on 5 and 6 from each other process steps are carried out simultaneously, i.e. the relaxation is superimposed on the differential local change of length of the profile. As a result of this process yields a steady increase in the length of the sample, which is proportional to all who joined the quantity of the component or, respectively, the average value of concentration profiles in a given time. In practice, the changing face profiles of the sample or appropriate to estwenno changes its length thermochemical processes, which, as carburizing, occur at high temperatures, close to the fully plastic response. Thermochemical processes, which occur at lower temperatures, as, for example, nitriding increases the proportion of elastic properties.

7 shows an example of a device for implementing the invention method using mechanical devices 4 length measurement. The sample 1 is under the action of the atmosphere and at a temperature thermochemical process in the zone 21. Gas atmosphere from which passes the component, influences from all directions of the respective arrows 2, on the side surface of the sample 1. Its lower end surface 12 of the sample adjacent to the base plate 31, which is connected through the holder 32 with the device 4 length measurement in such a way that prevents relative movement of the support plate 31 and the device 4 length measurement. During the diffusion component is the change in length of the specimen 1 in the longitudinal direction. The change in length from the highest points of the surface profile of the end sides 11 and 12 is transmitted to the rod 33, which transmits it to the device 4 length measurement.

In the case of the device 4 length measurement we can talk about, for example, capacitive or inductive measuring system which transmits the measured value in electric and are not represented in the drawings, the data processing system. The device 4 length measurement is located inside the zone 22, which is out of zone 21.

Fig shows the structure corresponding to the invention the device using the optical device 40 for measuring length. While structurally the same, compared with 7 parts are provided with identical positions. When this arrow 34 corresponds to the measuring rod 33 figure 7 and represents a measurement beam optical system, which may be, for example, by a laser beam.

Another measuring method for registration of the change of length of the specimen 1 is implemented using strain-gauge strips. They are applied in the longitudinal direction on the sample and then jointly undergo a change in length of the side surface of the sample. The importance of stretching after compensation of the temperature factor can then also be processed for the evaluation of the measured length changes.

Fig.9 shows the standard chart of changes in the time length of the sample, how it is measured, for example, a device corresponding to Fig.7, when the carburizing of steel sample SK. When this arrow 70 shows the time axis, and the arrow 71 - axis length changes. Section 73 of the curve indicates the length change that occurs in the heating process in an inert gas atmosphere and is accompanied by a transformation of the original structure is ture, moreover, according to the point 74, the structure is converted into austenite. Section 75 of the curve corresponds to the elongation at a constant temperature. Up to this point elongation curve corresponds to the usual dilatometric curve measurements.

At the point 76 of the inert gas atmosphere is replaced by carbonizing atmosphere, for example, a mixture of carbon monoxide, hydrogen and propane. Instantly shows the elongation of the sample, which, when sufficiently long processing time goes into saturation, as shown by section 77A of the curve. In this condition, the concentration in the whole body of the sample is in equilibrium with active carbon gas atmosphere. In the present example, it is assumed that the saturation is close to the limit of solubility of carbon in austenite, i.e. it is the line Azm metastable diagram of iron-carbon.

Section 78A of the curve corresponds to cooling of the sample, and at the point 79A begins the evolution of secondary cementite, and at the point 79b - perlite. In the above example, the value of saturation is zaevtektoidnoj area. If the saturation of the sample opposite is zaevtektoidnoj region, then the point 79A would be consistent with the allocation of ferrite.

In experiments on cementation, which have not been brought to equilibrium saturation with a gas atmosphere, so as the carburizing gas atmosphere for which inalas, for example, an inert gas, the portion of the curve after the point 76 ended abruptly before reaching saturation 77A and passed directly to a horizontal line. As to this point in time in the sample there is a concentration gradient, falling inside, the length change corresponds to the curve, which is similar to the curve of cooling of different carbon-containing alloys and has phase transitions, corresponding to points 79A, 79b.

Figure 10 shows the above-described experiments on the chart, change the length depending on temperature. When this arrow 72 indicates the axis of temperatures, and the arrow 71 - axis relative changes in length.

Region 731-761 curve represents the heating of the sample in an inert atmosphere, and the conversion to austenite is completed at the point 741. Between points 761 and a is carried out subsequent isothermal change of the length, which is associated with the cementation process. Plot a-a-a-791b curve corresponds to cooling of the sample after cementation with phase transitions at points a and 791b.

11 shows an exemplary device for measuring the length change of the sample respectively by the method according to the invention. The sample 1 has the end surface 12 on the support plate 31 and adjacent the other end surface 11 to the shaft 331, which in relation to the sample 1 represents the second of the ROS. Sample 1 during thermochemical process is exposed to high temperature, whereas the device length measurement, which can be installed on the cooled flange 324 that from their side ends gastight wall 5 thermochemical reactor, essentially, is under the influence of a temperature level close to room temperature, which creates a significant temperature gradient. Therefore, the length change of the sample coupled with changes in the length of the rod 331 and the holder plate 31 supports. To keep the magnitude of these factors is negligible, the spindle 331 is made of ceramics, for example, of quartz. This is of great importance that the end surface of the quartz rod, which is in contact with the end surface 11 of the sample 1, is fully polished and flat, and when this exceeds the diameter of the sample to ensure finding all points of the end surface 11 in contact with the end surface of the quartz rod.

To compensate, although minor, but still present due to the large length change the length of the rod 331 in the temperature field, the distance between the plate 31 supports and flange 324 is mounted by means of shaft 332, which mainly consists of the same sa the CSOs ceramic material, as the rod 331. As ceramic materials krupchitsy under mechanical load, the bearing plate 31 is located on a metal pipe 321 high heat resistance, which presses the metal ring 323 within the recess 324 push spring 325. Ceramic rod 322, which down through the metal pipe 321 is rigidly connected with the support plate 31, is adjusted because of this, the end metal bolt that is connected to the block 324. Thus, a large elongation of the metal pipe 321 when the temperature affects only the change of the compression spring 325, while the distance between the support plate 31 and the metal block 324 is set by a ceramic rod 322.

The actual length measurement is carried out in the example of figure 11 by induction due to the fact that the ceramic rod 331 is at the top of a cylindrical metal body 411, a move which is perceived inductive measuring coil 421 through the wall 420.

Additionally provided with a temperature sensor 6, such as a thermocouple in the shell, which passes through the input 61 of the flange 324 and is connected via a connection 62 to the data collection device. The measured values as the unit of length measurement, and the temperature sensor are not shown in the drawing in which trojstvo data collection, and then a corresponding computer program translated into the concentration profile of component in the sample.

A significant advantage of this method is the fact that the geometry of diffusion may vary within wide limits and, together with the activity and duration controlled, thermochemical process can be selected, for example, for tubes with wall thickness of 0.1 mm or solid cylindrical body with a diameter of 6 mm or more. In addition, the alloy of the sample can optionally be selected in accordance with the material of controlled items, so that the measurement results can be transferred directly to the behavior of the parts.

For example, the cementation process should show the following implementation of the relevant invention the control of the process.

In a short time carburizing, largely irrespective of the shape of parts may be made the assumption that the diffusion process as a one-dimensional non-stationary process. When a sufficiently large wall thickness, for example, a solid cylinder with a sufficiently large diameter, it is also true for the sample. The diffusion coefficient for a given material at a known temperature is constant, which if known boundary concentration of carbon may p the OSTO be calculated diffusion profile. The boundary concentration at equilibrium is a function of the activity of carbon gas atmosphere, which is calculated from the gas composition and through the characteristic solubility in steel when using the activity coefficient can be calculated in the concentration of carbon. However, the value of the coefficient of the transition of the substance of carbon from the gas atmosphere in the surface layer of the metal lattice is not known. Thus, the profile can be calculated only as indicated below. Based on the invention of the method in each time you know the amount of carbon that goes into the test body. From this obtained directly related to the unit of time and surface mass flux of carbon. Corresponding to the invention the device is directly measuring sensor With thread. On the basis of known data diffusion on the Arrhenius equation is calculated the diffusion coefficient of carbon in the alloy to the temperature of the experience. By solving the non-stationary diffusion equation for cylindrical coordinates is determined by the boundary concentration, which is at a known diffusion coefficient over time goes to the measured average carbon content. This boundary concentration through the nonstationary equation translates into about the Ile concentration within the geometry of the part.

It is clear that described above for the case of the cementation process can also be used for other thermochemical processes such as nitriding process.

If in the process of carburizing temperature changes, despite this, the change in carbon content can be accurately determined. To this end, the length change that occurs in the considered temperature region due to the linear expansion coefficient of austenite is subtracted from the total length change. The remainder of the measured length corresponds to the relative number of converts in the sample of carbon.

1. Method for continuous determination of the entrants in thermochemical processing of metal parts of the surrounding gas atmosphere and take details of the number of the component in which the sample, the longitudinal size of which greatly exceeds its transverse dimension, is exposed to the gas atmosphere, the measured change in time of the sample length in the longitudinal direction caused by the transition component of the gas atmosphere, and use the measured change in length to determine the amount of the component is transferred from the gas atmosphere in the sample, and the method is carried out isothermal or when changing the temperature, and the calculated offset by the change in length caused is by changing the temperature.

2. The method according to claim 1, characterized in that the change in surface profile that appears when set mode cooling of the sample, preferably the change in length of the specimen in the longitudinal direction, and/or the temperature range of this change is used to determine the number and distribution of transitioning into the sample component.

3. The method according to claim 1, characterized in that when using the sample tube forms the transition component is only through the outer side surface.

4. The method according to claim 1, characterized in that when using the sample tube forms the transition component occurs through the outer and inner side surfaces.

5. The method according to claim 1, characterized in that the component is carbon.

6. Device for the continuous determination coming from the surrounding gas atmosphere during thermochemical processing of metal parts and accept the details of the number of the component for the implementation of the method according to one of claims 1 to 5, includes clip sample, a longitudinal dimension which is substantially greater than its transverse dimension, and a system of length measurement for registration of the change in time of the sample length in the longitudinal direction with the computing unit.

7. The device according to claim 6, characterized in that clip sample has two supports, and the position of one who C supports fixed relative to the measurement system length.

8. The device according to claim 6, characterized in that at least one of the parts of the clamp of the sample is located inside the gas atmosphere.

9. The device according to claim 6, characterized in that the system changes the length of the outside of the gas atmosphere.

10. The device according to claim 6, characterized in that the sample is located inside a furnace installation for thermochemical processing.

11. The device according to claim 6, characterized in that the system of measuring the length of an optical system.

12. The device according to claim 6, characterized in that the measuring system length is a mechanical system.

13. The device according to claim 6, characterized in that there is a flowing channel, preferably in the form of a pipe, for a sample.

14. The device according to claim 6, characterized in that it has a temperature sensor.



 

Same patents:

FIELD: physics, measurement.

SUBSTANCE: invention is related to measuring equipment and is intended for measurement of heights of internal ribs (corrugations) of annular articles. Device for measurement of internal ribs heights consists of assembled casing, on which the following components are installed: measuring indicator with tip, basic supports and clamp with the possibility of displacement. At that casing is equipped with guide lines, in which clamp is installed arranged in the form of wheel installed in slider, basic supports are arranged in the form of generatrices of rotary bodies with the same diameter, have common axis of rotation and are installed in the casing with provision of clearance between ends that is symmetrical to axis of indicator tip. At that axis of indicator tip, axis of basic supports rotation, axis of wheel rotation and axis of guidelines symmetry are installed in one plane, and axes of wheel and basic supports rotation are parallel to each other and perpendicular to indicator tip axis.

EFFECT: provision of possibility of measurement of height and height difference of annular article rib along the whole perimeter.

4 cl, 3 dwg

FIELD: measuring technique.

SUBSTANCE: assemble comprises several groups of members including first group with the member of minimum size and several groups (second, third and so on) of members whose sizes differ by a given value.

EFFECT: expanded functional capabilities.

FIELD: engineering of measuring equipment, namely, engineering of incrementing means for measuring linear displacements.

SUBSTANCE: photoelectric incrementing bitmap transformer has body, measuring rod, guiding rod, bitmap mating device, consisting of measuring and indicating bitmaps with emitters and photo-detectors, platform, held on measuring rod, spring. On opposite ends of guiding rod rollers of same diameter are mounted - upper one and lower one, respectively, and inside the guiding rod longitudinal, through aperture is made, wherein with a gap relatively to its axis a spring is positioned, ends of which, rounding the rollers, are symmetrically held at both sides of platform, while axis of spring in place of ends holding is parallel to axis of guiding rod, also, lower roller is positioned in the hollow made in the body.

EFFECT: engineering of photo-electric bitmap transformer with compact position of constructive elements and extended functional capabilities.

2 dwg

FIELD: engineering of measuring equipment, namely, engineering of incrementing means for measuring linear displacements.

SUBSTANCE: photoelectric incrementing bitmap transformer has body, measuring rod, guiding rod, bitmap mating device, consisting of measuring and indicating bitmaps with emitters and photo-detectors, platform, held on measuring rod, closing spring, one end of which is held on one side of platform. Transformer is provided with additional spring of lesser rigidity in comparison to rigidity of closing spring, and moving rollers, mated, respectively, to closing and additional springs, plane of position of which is perpendicular to axes of rollers rotation. In guiding rod measuring force adjusting device is positioned in form of block with possible movement relatively to guiding rod and holding in place by means of screw for example, mounted in the groove of guiding rod, and a longitudinal, through aperture is made, wherein closing and additional springs are positioned, first ends of which are held on different sides of aforementioned block, and another end of additional spring is connected to platform on the side opposite to holding of end of closing spring. Roller of additional spring is mounted on axis of bracket, positioned at the end of guiding rod, with possible movement along the axis of the latter.

EFFECT: engineering of reliably operating bitmap transformer making it possible to decrease oscillations of measuring force, adjust measuring force, improve precision of measurements.

2 dwg

FIELD: measurement technology.

SUBSTANCE: device can be used for measuring internal sizes of members and units. Device for measuring linear sizes has case, measuring levers with tips, elastic members fixed to measuring levers, measuring converter. There is platform between measuring levers; additional elastic members are fixed at ends of the levers. Platform is cinematically connected with measuring converter.

EFFECT: simplified design; improved sensitivity; reduced sizes.

1 dwg

FIELD: the invention refers to textile industry particularly to means of controlling parameters of textile packing of cross reeling.

SUBSTANCE: the arrangement has a movable carriage with a hermetic cavity, filled with liquid. The cavity is connected with a pipe with a scale. In the carriage the re openings in which mobile probing rods are located. At moving the carriage one end of the mobile probing rod is leaned against the butt-end of surface of the controlling textile packing and with the other end the liquid is squeezed out of the cavity into the pipe. The volume of the squeezed liquid is inversely proportionate to the deviation of the form of the butt-end surface from stated. On each probing rod there are electrical contacts located in such a manner that in the extreme position of any probing rod a locking of its contact with the contact located on the carriage takes place. At that the ends of the probing rods are leaned against the controlling surface over the flexible tape movably fixed on the extreme probing rods.

EFFECT: the invention increases quality of production at operative controlling of parameters at the expense of receiving a generalized parameter characterizing the deviation of the form of the butt-end from stated.

1 dwg

The invention relates to the field of textile industry, in particular to the field of measuring equipment, and can be used to determine the average length of flax

The invention relates to measurement and can be used on car-repair enterprises in complete wheelset bogie freight wagons

The invention relates to a measurement technique, namely the incremental measurement of linear displacement

The invention relates to a technique of measuring the linear quantities

FIELD: measurement technology.

SUBSTANCE: according to method of contact-free optical measurement the object is placed between laser radiation source and photoreceiver. Power of laser radiation P is measured and compared with preset level of power P0 . Laser radiation is optically scanned into beam of parallel rays at the area where object finds its place and size of object is found from size of shade of object onto photoreceiver while correcting time of exposure from value of difference (P0-P). Device for realizing the method has laser, beam-splitting plate, short-focused cylindrical lens, output cylindrical lens, collimating lens, CCD, data processing unit, photoreceiving threshold unit.

EFFECT: improved precision of measurement.

5 cl, 1 dwg

The invention relates to the field of measurement technology and is used to determine the service life of nuclear reactors (RBMK) according to the criterion of exhaustion gap in the system process channel - graphite clutch

The invention relates to fiber-optic transmission systems in measurement technology and can be used to measure displacement of the object

Vocabulary sensor // 2107258
The invention relates to the field of measurement technology and can be used in automatic process control systems of industrial enterprises

The invention relates to measuring technique and can be used in machine building, ferrous and nonferrous metallurgy in the production of rent, rubber and chemical industry in the manufacture of tubular products without stopping the process

The invention relates to a device for measuring the size of the periodically moving object containing the optoelectronic measuring device that includes a transmitting-receiving elements located in at least one plane changes, perpendicular to the longitudinal axis of the object, and the processing unit, and the plane of the measuring portal is limited by at least two measuring beams arranged at an angle relative to each other

Fiber optic sensor // 2082086
The invention relates to the field of measurement technology, in particular to the field of fiber-optical measuring instruments

FIELD: metallurgy.

SUBSTANCE: invention refers to production of items out of pseudo-α or (α+β) titanium alloys, designed for continuous operation in friction pairs with polymer or metallic materials and biological tissues. First a stock is produced, then it is subject to thermo hydrogen treatment by means of saturation with hydrogen by thermo diffusion method till concentration of hydrogen reaches 0.5-0.9% in weight at temperature of 700-850°C. Then holding is carried out with successive cooling to an ambient temperature at the rate 0.1-10 deg/sec. Further there is performed firing in vacuum at not less, than 5-10-5 of mercury column at temperature of 550-700°C with holding within 4-20 hrs till concentration of hydrogen reaches not more, than 0.01 wt %. Polishing is carried out till obtaining of surface roughness parameter of Ra from 0.02 to 0.08 mcm. Then vacuum ion-plasma nitriding is executed at temperature of 300-700°C, till the thickness of nitrated layer is not less, than 50 mcm. With above described method there is produced an item containing nitrated surface layer consisting of nitrides of titanium of composition from Ti2N to TiN and sub-layer out of solid solution of nitrogen in titanium and a core.

EFFECT: creation of complex process facilitating high wear resistance and low friction ratio, also high corrosion resistance of items in corrosive, including biological, mediums.

17 cl, 2 dwg, 3 ex

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