Al-mg-si-strip for applications with high requirements to moulding capacity

FIELD: metallurgy.

SUBSTANCE: invention relates to the method for manufacturing of a strip, made of alloy of Al-Mg-Si, in which a bar for rolling is cast from alloy Al-Mg-Si, exposed to homogenisation, the bar for rolling heated to temperature of hot rolling, is exposed to hot rolling and then, if required, cold rolling to its final thickness, at the same time the hot strip has temperature of not more than 130°C directly at the outlet from the last stage of hot rolling, preferably the temperature of not higher than 100°C, afterwards the strip is wound at this or lower temperature.

EFFECT: method makes it possible to perform aluminium strips from alloy Al-Mg-Si, which have higher relative extension and accordingly higher extents of deformation when structural metal sheets are made.

15 cl, 5 tbl, 4 dwg

 

The invention relates to a method of manufacturing a strip of alloy Al-Mg-Si, in which the cast ingot for rolling of the alloy Al-Mg-Si ingot for rolling is subjected to homogenization, is brought to a temperature rolling and subjected to hot rolling and then optional cold rolling to the final thickness. The invention also relates to an aluminium strip made of an alloy of Al-Mg-Si, and its best use.

In particular, in the automotive industry, as well as in other applications, such as aircraft construction and manufacture of rail vehicles, requires metal sheets made of aluminum alloys, which not only have high strength values, but also have good characteristics formemost and allow a high degree of deformation. In typical automotive applications are the body and chassis. For visible colored components, such as body sheet metal, which can be seen from the outside, with the deformation of the material surface should not worsen its appearance associated with defects after dyeing, such as moving strip or broadcast. This is particularly important, for example, when aluminum sheets are used for the manufacture of engine and other body parts of the vehicle. However, is it also limits the choice of material, if we are talking about aluminum alloys. In particular, Al-Mg-Si alloys, the main components of which are magnesium and silicon, have relatively high strength and, at the same time, good performance of formemost and exceptional resistance to corrosion. Al-Mg-Si alloys are alloys of types AAHHH, for example types AA, AA, AA, AA and AA. Aluminum strip is usually made of alloy Al-Mg-Si by casting ingot for rolling, homogenization of the ingot for rolling and subsequent hot rolling of the ingot for rolling and cold rolling the warm lanes. The ingot for rolling homogenized for more than one hour at a temperature of from 380 to 580°C. After the final solid solution annealing and subsequent quenching and natural aging at approximately room temperature for a period of not less than three days, the band is ready for use in state T4. The T6 condition obtained after quenching by artificial aging at temperatures of from 100 to 220°C

The problem is that the hot-rolled aluminum strip, made of alloys of Al-Mg-Si, contain large selection of Mg2Si, which would break and reduce in size during the subsequent cold rolling as a result of high degree of their deformation. Hot strip alloy Al-Mg-Si is usually produced with a thickness of from 3 to 12 mm and then n is prevlayout on stage cold rolling with a high degree of deformation. Since the temperature range in which are formed the Al-Mg-Si phase, in the conventional hot rolling is overcome very slowly generated during this phase are very large. Temperature range for formation of the above phases depends on the alloy, but is located between 550 and 230°C. it Was shown experimentally that these major phases in a hot strip worsen the elongation of the final product. This means that previously it was not possible to use the characteristics of formemost aluminum strips obtained from alloys of Al-Mg-Si.

The aim underlying the present invention is thus to provide a method for manufacturing aluminum strip of alloy Al-Mg-Si, which would have had higher relative elongation in state T4 and this extension would provide a higher degree of deformation in the manufacture of, for example, structured components. Another aim underlying the present invention is to offer useful applications sheet metal made of aluminum strip according to the invention.

According to the first disclosure of the present invention, the purpose of the method of manufacturing a strip of the above described alloy Al-Mg-Si is achieved by the fact that, immediately after the exit from the last pass of hot rolling hot n the Loos has a temperature, not exceeding 130°f, mostly, the temperature not exceeding 100°C, after which the hot strip wound at this or a lower temperature.

It was found that the size of precipitates of Mg2Si in a hot strip alloy Al-Mg-Si can be significantly reduced by quenching, in other words with accelerated cooling. At fast cooling from the temperature of the hot band between 230 and 550°C to a temperature not higher than 130°C, mainly not higher than 100°C, the output from the last pass of the hot rolling, the microstructure of the hot strip is frozen, thanks to a large selection of more than cannot be formed. After annealing and hardening, solid solution to obtain the final thickness of the finished aluminum strip has significantly improved elongation at normal strengths in state T4 and the same or even better hardening during aging in the T6 condition. This combination of properties on the strips are made of alloys of Al-Mg-Si, has not previously been achieved.

According to one of preferred embodiments of the method according to the invention, the cooling operation is carried out during the last two passes of rolling, i.e. cooling to 130°C and below takes seconds and in any case not more than five minutes. It was found that using this method increased consider is inoe elongation at normal values of tensile strength and yield strength in state T4, as well as improved proclaimest with aging in the T6 condition can be achieved by a particularly high degree of process reliability.

According to the first variant of the method according to the invention, particularly economically advantageous arrangement for implementing the method is created when hot streak quenched using at least one plate cooler and loaded emulsion of the passage of the hot rolling to a temperature of the winding. Plate chiller contains a number of cooling and lubricating nozzles which spray the emulsion rolling mill for aluminium strip. Plate cooler is often present on the rolling mill with the aim of cooling the hot rolled strips up to temperature before rolling stage hot rolling and to establish the temperature of the winding. The method according to the invention can be carried out in conventional systems without any special additional equipment. By definition, the temperature of the hot rolling above the recrystallization temperature of the metal, which in the case of aluminium means that this temperature is above approximately 230°C. However, according to the present invention, the temperature of the winding at 130°C significantly below these standard terms and conditions for the method.

If the temperature of the hot rolling hot strip reaches at least 230°C, preferably above 400°C, before the penultimate passage of the hot rolling, according to the following variant of the method according to the invention, it is possible to ensure the presence hardened in a hot strip of very small precipitates of Mg2Si, as predominant components of alloy magnesium and silicon are present in the aluminum matrix at these temperatures in a dissolved state. This is the preferred state of the hot strip "frozen" as it had been in early stages of hardening.

The thickness of the finished hot strip equal to from 3 to 12 mm, mainly from 3.5 to 8 mm, which means that for the cold rolling can be a standard rolling mills.

Used aluminum alloy mainly refers to the type Aahhh, mainly AA, AA, AA, AA or AA. Common property of the alloys of type Aahhh is that they have an extremely good formability, characterized by high relative movements in state T4 and very high strengths and limits the yield of the ready for use condition T6, for example, after artificial aging for 30 min at 205°C.

According to another variant implementation of the present invention the finished laminated aluminium strip is subjected to heat treatment in which the aluminum is heated to pace the atmospheric temperature above 100°C, then his wound and subjected to aging at temperatures above 55°f, mostly above 85°C. This variant of the method allows you to enter after natural aging shorter heat-up phase at lower temperatures to update the status of T6, in which the aluminum sheet or strip after forming parts used for a purpose. To accomplish this, these are subjected to rapid aging of the aluminum strip is heated only 20 min to temperatures of about 185°C to achieve higher values of yield strength in T6 condition. However, the values of A80elongation at break aluminum strips, made with the help of this variant of the method according to the invention, slightly below 29%. However, aluminum strip produced according to the invention, is noteworthy in that after aging in the state T4 it still retains a very good uniform elongation Agover 25%. The expression "uniform elongation Ag" refers to the maximum elongation of the sample, which during the tensile test is not observed no sign of narrowing. In other words, the sample is gently stretched in a uniform range extension. Previously, these materials did not reach the values for uniform elongation more 22-23%. Even in the United linnie is a critical factor in the behavior of the molding, because it determines the maximum degree of deformation that can be applied to the material in practice. Thus, the method according to the invention can be used to obtain aluminum strip with very good characteristics formemost, which can be translated in the T6 condition by a process of accelerated artificial aging (185°C/120 min).

Aluminum alloy type AA includes the following alloy components in the corresponding wt%:

0,25%≤Mg≤0,6%,

1,0%≤Si≤1,5%,

Fe≤0,5%,

Cu≤0,2%,

Mn≤0,2%,

Cr≤0,1%,

Zn≤0,1%,

Ti≤0,1%

the rest of Al and unavoidable impurities, comprises a total of not more than 0.15% and not more than 0.05% separately.

When the magnesium content less than 0.25 wt.% the strength of aluminium, designed for structural applications too low, but, on the other hand, when the content of magnesium above 0.6 wt.% deteriorates formability. Silicon and magnesium together to a significant extent responsible for proclaimest aluminum alloy and consequently also for high strength, which is achievable in the case of application, for example after firing paint. When the content of Si is less than 1.0 wt.% proclaimest during aging aluminum strip is reduced, resulting in the application can be achieved only lower strength properties. However, the Si content of more than 1.5 wt.% results the problems with casting, concerning the production of ingots for rolling. The fraction of Fe in order to prevent the formation of large allocations should be limited to not more than 0.5 wt.%. The limit of the copper content up to 0.2 wt.% leads, in particular, to improved corrosion resistance aluminum alloy special kind. Magnesium content less than 0.2 wt.% reduces the tendency to form larger manganese precipitates. Although chromium is responsible for the fine microstructure, it should be limited to 0.1 wt.%, to prevent this, the formation of large precipitates. On the contrary, the presence of manganese resulted in improved weldability of aluminum strip according to the invention by reducing its tendency to cracking and its ability to hardening. The decrease of zinc content to not more than 0.1 wt.% increases the resistance to corrosion of aluminum alloy or completed sheet metal in the appropriate application. On the contrary, titanium during casting leads to grinding grain, but to provide easy casting aluminum alloy, titanium should be limited to not more than 0.1 wt.%.

Aluminum alloy type AA includes the following ingredients (wt.%):

0,35%≤Mg≤0,6%,

0,3%≤Si≤0,6%,

0,1%≤Fe≤0,3%

Cu≤0,1%,

Mn≤0,1%,

Cr≤0,05%,

Zn≤0,10%,

Ti≤0.1%

the rest of the Al is inevitable impurities, totaling not more than 0.15% and not more than 0.05% separately.

The combination of a well-defined content of magnesium with lower Si content compared with its content in the first embodiment, and is strictly a given Fe gives aluminum alloy, which can be particularly effectively prevented the formation of precipitates of Mg2Si after hot rolling, thereby producing a metal sheet having improved elongation and high limits to yield compared to traditionally produced in the leaves. Lower the upper limits of the alloy components Cu, Mn and Cr reinforce the effect of the method according to the invention. As regards the influence of the upper limit for Zn and Ti, it is possible to refer to the allegations concerning the first variant implementation of the aluminum alloy.

Aluminum alloy type AA includes the following ingredients of the alloy (wt.%):

0,4≤Mg≤0,8%,

0,3%≤Si≤0,6%,

Fe≤0,35%

Cu≤0,25%,

0,05%≤Mn≤0,20%,

Cr≤0,20%,

Zn≤0,10%,

0,05%≤V≤0,20%,

Ti≤0.1%

the rest of Al and unavoidable impurities, comprises a total of not more than 0.15% and not more than 0.05% separately.

Aluminum alloy type AA includes the following ingredients of the alloy (wt.%):

0,6%≤Mg≤1,0%,

0,8%≤Si≤1,2%,

Fe≤0,45%

Cu≤0,10%,

Mn≤0,15%,

Cr≤0,10%,

Zn≤0,20%,

Ti≤0.1%

the rest of Al and inevitable is remesi, totaling not more than 0.15% and not more than 0.05% separately.

Aluminum alloy type AA includes the following ingredients of the alloy (wt.%):

0,5%≤Mg≤1,0%,

0,7%≤Si≤1,1%,

Fe≤0,40%

0,50%≤Cu≤0,90%,

0,15%≤Mn≤0,45%,

Cr≤0,10%,

Zn≤0,15%,

Ti≤0.1%

the rest of Al and unavoidable impurities, comprises a total of not more than 0.15% and not more than 0.05% separately. Due to the higher copper content of the alloy AA usually shows higher values of strength in the state of application of the T6, but it should be classified as more prone to corrosion.

Components of all aluminum alloys are chosen in a special way to suit different applications. As noted above, strip, of aluminium alloys, which were produced according to the method of the invention have a particularly high values of relative elongation able T4 in combination with a distinct increase of the yield stress, for example after artificial aging at 205°C/30 minutes The same applies to the aluminum strips in state T4, subjected to annealing solid solution after heat treatment.

According to the second idea of the present invention, the above aim is achieved by an aluminum band, consisting of alloy Al-Mg-Si that T4 is characterized by elongation to break (A80equal is at least 30% with the yield strength (Rp0.2) from 80 to 140 MPa. Ready-to-use state T4 is typically accomplished by annealing the solid solution by quenching and subsequent aging at room temperature for at least three days, because by this point the properties of the metal sheets or strips, subjected to annealing in the solid solution becomes stable. The combination of lengthening A80to break and yield strength Rp0.2 aluminum strip according to the invention was not achieved with the previously known alloys Al-Mg-Si. At the same time, the aluminium strip according to the invention allows the maximum degree of deformability due to high values of relative elongation at maximum yield stress Rp0.2 in the completed sheet and details.

One of the options for the implementation of Mg-Si aluminum strip differs particularly advantageous characteristics of formemost due to the fact that the uniform elongation of Agexceeds 25%. Uniform elongation is a critical factor in determining the maximum degree of deformability aluminum strip and from the sheet metal in the manufacture of parts, because the production process is extremely important to avoid uncontrolled contractions. Aluminium strip according to the invention has a particularly high strain capability in terms of narrowing and sledovatel is, it can be molded with greater process reliability.

Being able T6, i.e. ready for use, the aluminium strip according to the invention mainly has a yield point Rp0.2 above 185 MPa with a relative lengthening of the A80equal to at least 15%. These values were measured on the aluminum strips made according to the invention, in the T6 condition, after the surgery, artificial aging for 30 min at 205°C and subsequent solid solution annealing and quenching (state T4). Due to the high yield strength in T6 condition and great values relative elongation able T4 aluminum strip according to the invention is particularly suitable for use, for example, in the automotive industry.

According to another variant embodiment of the invention, subjected to solid solution annealing and tempered aluminum in the T6 condition after artificial aging at 205°C/30 min is the difference between the limits of fluidity in the States of T6 and T4 is equal to at least 80 MPa. The increase in yield stress at the transition from T4 to T6 condition is especially great at aluminum strip according to the invention. Therefore, the aluminum strip according to the invention itself can be easily molded in a state T4 and may continue to be transformed is Oh very durable for the application of state (T6) using artificial aging. With respect to the forming operations of high complexity and the need for high values of strength and fluidity, for example, in automotive industry, good proclaimest is particularly advantageous for the production of complex parts. Subjected to rapid ageing Mg-Si aluminum strip with exceptional performance formemost can be made, if obtained according to the invention the strip is subjected after its manufacturing operations annealing solid solution, followed by heat treatment and has the uniform elongation Agmore than 25% when the yield strength Rp0.2 from 80 to 140 MPa in state T4. As noted above, in this embodiment, it is possible to produce Mg-Si-aluminium strip, which is capable of rapidly aging and at the same time, has very good formability. Operation of artificial aging to create a state T6 can be carried out at 185°C for 20 min, which results in the desired increase of the yield strength.

If, as it takes place in another embodiment, the aluminum strip is characterized by the lengthening of the Agmore than 25% in the rolling direction, across the direction of rolling and diagonally to the direction of rolling, there is a possibility isotropic formemost.

Aluminum Polo is s mainly have a thickness of from 0.5 to 12 mm Aluminum strip thickness from 0.5 to 2 mm are mainly used in the automotive industry, for example, for body parts, while the aluminum strip of greater thickness, from 2 to 4.5 mm may be suitable for the production of, for example, parts of the chassis in the automotive industry. Individual parts, having a thickness up to 6 mm, can be produced from the cold strip. Along with them for special applications can be used aluminum strip with even thickness up to 12 mm are very thick aluminum strip can usually be done only with the help of hot rolling.

According to another variant implementation of the aluminium strip according to the invention, made of alloy type Aahhh, mainly AA, AA, AA, AA or AA. The benefits of these aluminum alloys are disclosed in the description of the method according to the invention.

Thanks to the wonderful combination of good formemost able T4, high corrosion resistance and high values of yield strength Rp0.2 in a state of fitness for use (T6 condition), the above objective is achieved according to a third idea of the present invention, by using a metal strip made of aluminum strip according to the invention, as any of the component chassis or structural details of the panel in the design of the car, aircraft or railway carriage, in particular as a component, chassis, exterior or interior panels in the automotive industry, mainly as a structural element of the body. High limits yield strength Rp0.2 and good surface properties, even after molding with high degrees of deformation is primarily useful for visible body parts, hoods, bumpers, etc. and outer panels of railway cars and planes.

There are many possible ways for improvement and development of the method and the aluminum strip according to the invention, and to use it made of sheet metal. On this issue should be addressed as to the claims subordinate to the paragraphs 1 and 6 of the claims and to the description of typical embodiments in conjunction with the drawing.

The only figure 1 is a flow diagram of one of the typical embodiments of the method according to the invention for the manufacture of strips made of Mg-Si aluminum alloy, in the stages (a) production and homogenization of the ingot for rolling; (b) hot rolling; (c) cold rolling; and d) annealing to solid solution hardening.

First cast ingot 1 for rolling of an aluminium alloy containing the following components is, for example (wt.%):

0,35%≤Mg≤0,6%,

0,3%≤Si≤0,6%,

0,1%≤Fe≤0,3%

Cu≤0,1%,

Mn≤0,1%,

Cr≤0,05%,

Zn≤0,1%,

Ti≤0.1%

the rest of Al and unavoidable impurities, comprises a total of not more than 0.15% and not more than 0.05% separately.

Made it through the ingot for rolling homogenized in a furnace 2 at a temperature of homogenization of about 550°C for 8 hours, resulting alloy components completely homogeneous distributed across ingot for rolling (figa).

On fig.1b shown as bar 1 for rolling this variant of the method according to the invention is subjected to hot rolling by reversing through hot rolled mill 3, where the ingot reaches during hot rolling temperature from 230 to 550°C. In this embodiment, hot strip 4 after escaping from the hot roll 3 and before the penultimate passage of the hot rolling predominantly has a temperature of at least 400°C. Tempering warm strip 4 takes place mainly when the temperature of the hot strip at least 400°C using a plate cooler 5 and the work rolls of hot rolled mill 3. Plate cooler 5, which is shown only schematically, spraying hot streak 4 cooling proctocol emulsion and provides rapid cooling of the strip 4. Work rolls for rolling mill 3 are impacted by the emulsion and to omnitele cool the strip 4. After the last pass of rolling on the output from the plate cooler 5' in this example, the hot strip 4 has a temperature of only 95°C, and then is wound on the winder 6.

Because hot strip 4 has a temperature of not higher than 130°C., or not higher than 100°C immediately after the exit from the last pass of hot rolling or possibly is cooled to a temperature not higher than 130°C., or not higher than 100°C during the last two passes of hot rolling using a plate cooler 5 and the work rolls of hot rolled mill 3, the crystalline microstructure of the hot strip 4 is frozen in the state in which it is, since no additional energy in the form of heat for the subsequent stages of selection are not available. Hot strip thickness from 3 to 12 mm, mainly from 3.5 to 8 mm, is wound on the winder 6. As mentioned above, the temperature of the winding in this embodiment, is below 95°C.

In the method according to the invention in wound hot strip 4 impossible the formation of precipitates of Mg2Si or may form only a small quantity of discharge of Mg2Si. Hot strip 4 has a crystalline state, which is very well suited for further processing, and can be unwound through the coil 7, is directed, for example, on cold rolled mill 9 click again wound on the winder 8 (figs).

The obtained cold-rolled strip 11 leaves and then goes to solid solution annealing and quenching 10 (fig.1d). To this end, the band once again leaves the coil 12, is subjected to solid solution annealing in the furnace 10, quenched and returns to the coil 13. Then, after natural ageing at room temperature aluminum strip can be sent to the consumer in state T4 with a maximum formability. Alternatively (not shown) aluminum strip 11 may be separated into individual sheets, which will then go after natural ageing in state T4.

In case of a thicker aluminum strips, for example for use in chassis or for parts like base frame, alternatively, may be performed step-by-step annealing, immediately after which the leaves will powerhouse hardening.

In state T6 aluminium strip or aluminium panel is heated to a temperature of from 100 to 220°C in the operation of artificial ageing with the aim of obtaining the maximum values of the yield strength. Artificial ageing can, for example, be carried out at 205°C/30 min

Aluminum strip produced according to a variant of implementation, have a thickness after natural aging, for example, from 0.5 to 4.5 mm, the Thickness of the strip from 0.5 to 2 mm are used in the automotive industry, as a rule the ILO for automotive applications, and the thickness of the strip from 2.0 to 4.5 mm is used for chassis components. For both applications increased value relative have a decisive advantage in the production of parts, as most of the operations sheets includes extensive molding, but at the same time important is a high strength condition (T6) application of the final product.

Table 1 shows the compositions of aluminum alloys, which were made of aluminum strip using traditional ways and methods of the invention. Also shown in table 1 components of the alloy, the rest is composed of aluminium foil is aluminum and impurities, the individual amounts not exceeding 0,05 % by weight and the total amount of which does not exceed 0.15 weight %.

0,057
Table 1
BandSi, wt.%Fe, wt.%Cu, wt.%Mn, wt.%Mg, wt.%Cr, wt.%Zn, wt.%Ti, wt.%
4091,290,170,0010,29<0,0005<0,0010,02
4101,300,170,0010,0560,29<0,0005<0,0010,0172
491-11,390,180,0020,0620,300,00060,010,0158
491-111,400,180,0020,0630,310,00060,01040,0147

Bands (samples) 409 and 410 is manufactured according to the method of the invention, according to which in the last two passes of hot rolling hot strip is cooled from about 400 to 95°C using a plate cooler and the hot rolls, and then leaves. The measured values for these bands indicated in table 2 as "sober". The strip is subjected to cold rolling to the final thickness 1,04 mm

Bands (samples) 491-1 and 491-11 manufactured using conventional hot rolling and method of cold rolling and marked as "Trad".

The results of mechanical properties are shown in table 2, clearly show the difference in the achievable values of the relative elongation of A80.

Table 2
BandT4T6 205°C/30 min
Thickness (mm)Rp0.2 (MPa)Rm(MPa)Ag(%)A80(%)Rp0.2 (MPa)Rm(MPa)A80(%)ΔRp0.2 (MPa)
409Image1,0410022026,331,3187 25116,287
410Image1,049821725,630,319525615,597
491-1Trad1,049220223,127,818023514,788
491-11Trad1,048819623,0

In order to achieve the status of T4 strip is subjected to solid solution annealing and subsequent quenching, followed by natural aging at room temperature. The T6 condition is achieved by artificial aging for 30 min p and 205°C.

It was found that favorable microstructure, which was created in pages 409 and 410 using the method according to the invention, not only provides a higher yield strength Rp0.2 and increased strength Rm, but also makes possible increased elongation A80. This microstructure has the effect of a particularly advantageous combination of high relative elongation of A80to break equal to at least 30% or at least 30% at very high values of the yield strength Rp0.2: from 80 to 140 MPa. In state T6 yield strength can be increased to more than 185 MPa, in which case the relative elongation of A80still above 15%. Proclaimest when ΔRp0.2 is 87 or 97 MPa shows that embodiments of the invention show a very high increase of the yield strength of artificially aged T6 condition during artificial aging at 205°C/30 min, despite the increased value of relative elongation greater than 15%.

Comparison of uniform movements Agstrips according to the invention and traditional bands also shows that under uniform elongation of Agwith values more than 25% of the strip of the invention 409 and 410 is significantly superior to traditional bands, for which the measured value is equal to 23%. Table 2 shows the mean is to uniformly extend across the direction of rolling. Additionally, the values above 25% for uniform elongation Agon the diagonal and in the rolling direction were noted for bands not shown in table 2, which were measured by the method according to the invention. These results emphasize the exceptional formability strips according to the invention.

The value of Agand A80relative elongation to break values Rp0.2 yield strength and value Rm limit tensile stress in the following table are measured according to DIN EN.

The measured values are confirmed in state T4 with measurements made by other bands. Aluminum alloy strips A and B had the following composition:

0,25%≤Mg≤0,6%,

1,0%≤Si≤1,5%,

Fe≤0,5%,

Cu≤0,2%,

Mn≤0,2%,

Cr≤0,1%,

Zn≤0,1%,

Ti≤0,1%

and the rest of Al and unavoidable impurities, comprises a total of not more than 0.15% max 0.05% separately.

Bands A and B were subjected to quenching in hot condition to 95°C using the method according to the invention during the last two phases of compression, after which the wound and then subjected to cold rolling to a final thickness of 1.0 mm and 3.0 mm, respectively. To achieve the status of T4 bands A and B were subjected to annealing in the solid solution and then naturally aged with subsequent hardening.

Both bands were measured the following values:

Table 3
BandT4
Thickness (mm)Rp0,2 (MPa)Rm(MPa)And80(%)
A1,010722131,1
B3,010821232,0

Additional increase of the values of A80relative elongation shows how perfect these aluminum strip is suitable for the manufacture of parts, which have a high degree of deformation in state T4 during the production process should be combined with the maximum tensile Rm tensile and limits yield strength Rp0.2 in the T6 condition.

Along with this, a study was conducted of other aluminium bars, subjected to additional heat treatment that is performed on the aluminum band mainly immediately after receipt of the product, for example directly after annealing the firmness of the Dogo solution and quenching. For this purpose, the aluminum strip was heated briefly to a temperature above 100°C and then wound at a temperature above 85°C (in this case at 88°C) and held natural aging.

Table 4 shows the composition of the strip 342, which was subjected to a further heat treatment after solid solution annealing and quenching.

Table 4
BandSi wt.%Fe wt.%Cu wt.%Mn wt.%Mg wt.%Cr wt.%Zn wt.%Ti wt.%
3421,30,170,000,060,3≤0,0005≤0,0010,02

Heat treatment, called the stage of preliminary roasting, in fact, led to the deterioration of the characteristics of elongation before rupture, as in this case, the lengthening of the A80before the break was less than 30%. Unexpectedly uniform elongation of the aluminum strip R save the moose above 25%, ie has not changed in comparison with the image that has not been subjected to heat treatment, as shown in table 5. Uniform elongation is a very important factor in forming aluminum strip in part because improved uniform elongation makes possible a higher degree of deformation and due to this either increases the process reliability or reduces the number of stages of formation.

Table 5 shows the various measured values. On the one hand, three measurements were taken at the beginning of the band R-VA and at the end of the strip R-VE. In the "Status" column indicates that the band were able T4, i.e. were subjected to solid solution annealing and quenching with subsequent natural aging for 8 days at room temperature. Strips were cut from the beginning of the band and the end of the strip and measured in the longitudinal direction (L), i.e. in the direction of rolling, across the direction of rolling (Q) and diagonally to the direction of rolling (D). It was found that while in some cases there was a decrease of the values of A80mmelongation to break of up to less than 30%, a uniform elongation of Agwas still a great 25% when measured in all directions and unexpectedly remained constant compared with the elongation before rupture of the strip, which was not heat treated.

Table 5Band/positionStatePositionao(mm)Rp0.2 (MPa)Rm(MPa)Ag%A80mm%R-VAT4 (8d RT)Lwith 1.00997209to 25.328,9R-VAT4 (8d RT)Q1,0069020625,528,5R-VAT4 (8d RT)D1,0059220725,629,1R-VET4 (8d RT)L1,00295208 30,1R-VET4 (8d RT)Q1,00089204to 25.328,3R-VET4 (8d RT)D1,0009020525,729,8

At subsequent stages of artificial aging the T6 condition was reached after 20 min at 185°C. Typical values for yield stress tensile, as measured in the T6 condition, were higher than 140 MPa after artificial aging and above 165 MPa after artificial aging, and then further stretching by 2%. Aluminum strip produced according to the invention, which was subjected to heat treatment, combines, therefore, two important properties. In state T4 is she is very easily deformed due to the high uniform elongation and at the same time it reaches the desired strength after artificial aging for 20 min at 185°C.

1. A method of manufacturing a strip of alloy Al-Mg-Si, in which the alloy Al-Mg-Si cast ingot for rolling, put it in the homogenization, the ingot for rolling, brought to the temperature of the hot rolling, is subjected to hot rolling and then if necessary, conduct cold rolling to the final thickness, characterized in that immediately upon exit from the last pass of the hot rolling hot strip has a temperature of not higher than 130°C, mainly not higher than 100°C, after which the hot strip wound at this or a lower temperature.

2. The method according to claim 1, characterized in that the hot strip is quenched to a temperature output using at least one plate cooler and loaded emulsion pass hot rolling.

3. The method according to claim 1 or 2, characterized in that the temperature of the hot rolling process before cooling during hot rolling and, in particular, before the penultimate passage of the hot rolling is at least 230°C, mainly above 400°C.

4. The method according to claim 1 or 2, characterized in that the thickness of the finished hot strip equal to from 3 to 12 mm, mainly from 3.5 to 8 mm

5. The method according to claim 1 or 2, characterized in that the aluminum alloy is an alloy type Aahhh, mainly AA, AA, AA, AA or AA.

6. The method according to claim 1 or 2, characterized in that after the finishing rolling aluminum strip is subjected to heat treatment in which the aluminum strip is heated to t is mperature above 100°C, then wound and subjected to aging at a temperature above 55°C, mostly above 85°C.

7. Aluminum strip containing alloy of Al-Mg-Si, in particular, manufactured by the method according to any one of claims 1 to 5, characterized in that the aluminum strip in state T4 has a relative elongation A80 to break equal to at least 30%, with a yield strength Rp0.2 from 80 to 140 MPa.

8. Aluminum strip according to claim 7, characterized in that the aluminum strip in state T4 has a uniform elongation Ag, a large 25%.

9. Aluminum strip according to claim 7 or 8, characterized in that subjected to annealing in solid solution and tempering of aluminum strip in the T6 condition after artificial aging at 205°C/30 min has a yield point Rp0.2 of more than 185 MPa.

10. Aluminum strip according to claim 7 or 8, characterized in that subjected to annealing in solid solution and tempering of aluminum strip in the T6 condition after artificial aging at 205°C/30 min is characterized by the difference ΔRp0.2 in yield strength between T6 and T4, equal to at least 80 MPa.

11. Aluminum strip containing alloy of Al-Mg-Si manufactured by the method according to claim 6, characterized in that the aluminum strip has a uniform elongation Ag more than 25% when the yield strength Rp0.2 from 80 to 140 MPa.

12. Aluminum strip according to claim 8 or 11, characterized in that the aluminum is I strip has a uniform elongation Ag more than 25% in the rolling direction, across the direction of rolling and/or diagonally to the direction of rolling.

13. Aluminum strip according to claim 7 or 11, characterized in that the aluminum strip has a thickness of from 0.5 to 12 mm

14. Aluminum strip according to claim 7 or 11, characterized in that the aluminum strip consists of alloy type Aahhh, mainly AA, AA, AA, AA or AA.

15. The use of aluminum strip according to any one of claims 7 to 14 as the sheet metal for the manufacture of a structural element in the automotive, aircraft, or railcar industry.



 

Same patents:

FIELD: metallurgy.

SUBSTANCE: method for obtaining composite material based on an aluminium matrix involves obtaining of a mixture of aluminium powders or its alloy and carbon nanotubes, sintering of the obtained mixture with formation of a briquette with its further rolling; with that, the mixture of powders is sintered by hot pressing in protective medium at the temperature comprising 0.6-0.99 of the melting temperature of aluminium powder or its alloy, and at pressure of 20-100 MPa during 10-300 minutes; the formed briquette is subject to cold rolling.

EFFECT: invention allows reducing the time for obtaining composite material and providing high mechanical properties.

10 cl, 2 ex

FIELD: metallurgy.

SUBSTANCE: product from deformed aluminium alloy consists of the following: 3.6-4.0 wt % Cu, 1.1-1.2 wt % Li, 0.4-0.55 wt % Ag, 0.25-0.45 wt % Mg, 0.4-0.6 wt % Zn, 0.2-0.4 wt % Mn, and 0.05-0.15 wt % Zr, and aluminium and secondary elements and impurities are the rest.

EFFECT: improved combination of strength and viscosity of aluminium alloy.

14 cl, 5 dwg, 8 tbl, 2 ex

FIELD: metallurgy.

SUBSTANCE: proposed method comprises casting the ingots of alloy containing the following components in wt %: zinc - 6.-4.1, magnesium - 0.6-1.1, manganese - 0.2-0.5, zirconium - 0.05-0.12, chromium - 0.05-0.15, copper - 0.1 -0.2, titanium - 0.01 -0.06, molybdenum - 0.01 -0.06, aluminium making the rest, at the temperature of 690-710°C and casting rate of 25-50 mm/min. Ingots are homogenised at 450-470°C for 8-12 hours and subjected to hot forming at 10-530°C and outflow rate of 0.1-4.0 m/min. Besides it includes air or air-water mix quenching and two-step ageing: at 90-110°C for 6-12 hours and at 160-190°C for 4-10 hours.

EFFECT: production of log parts with high operating properties.

4 cl, 1 ex, 6 tbl, 4 dwg

FIELD: metallurgy.

SUBSTANCE: recrystallised rolled sheet of aluminium alloy 2xxx features height not exceeding 12.7 mm (0.5 inch). At least 60% of said rolled sheet are recrystallised grains. Sid rolled stock features brass and Goss textures. Note here that brass texture makes at least 10 and is larger than Goss texture. Proposed method comprises hot rolling and cold processing of aluminium 2xxx alloy sheet, subjecting said sheet to first recrystallisation annealing, at least one stape (i) of cold processing and (ii) reducing annealing, (d) second recrystallisation annealing and (e) age-hardening.

EFFECT: recrystallised rolled sheet of aluminium alloy 2xxx with better strength and ductility.

44 cl, 21 dwg, 1 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: alloy contains, wt %: 3.5-4.5 zinc, 3.5-4.5 magnesium, 0.6-1.0 copper, 2.0-3.0 nickel, 0.25-0.3 zirconium, aluminium - balance, at the same time after strengthening thermal treatment the alloy has yield point of 570 MPa, strength limit of 600 MPa, hardness of 160 HY, and after deformation at 440-480°C with speed of 0.001-0.01 1/s the alloy has elongation of more than 500%.

EFFECT: production of alloy with equiaxial homogeneous fine-grain structure.

4 ex

FIELD: process engineering.

SUBSTANCE: invention relates to metallurgy, particularly, to production of thin-wall pipes. Proposed method comprises forming and piercing of solid ingot in container insert by its needle, press ring plate and press ram, as well as quenching, straightening and artificial ageing. Prior to forming with piercing, ingot arranged in said contained is compacted by cupped blank arranged between said ring plate and ram at the needle with aligned ends of the needle and ring plate, and is removed after compaction. Note here that straightening of quenched tube is performed by gaging the tube OD to the rate of deformation of 0.5-2.5.

EFFECT: high strength and precision.

1 dwg, 1 tbl

FIELD: metallurgy.

SUBSTANCE: proposed method comprises cooling blanks from quenching temperature to 430°C at the rate of 130-150°C/h, holding at said temperature for 3 min, cooling in water at 90-100°C, and final cooling to 25°C, and ageing. Note here that final cooling is executed between 5mm-thick steel plates with overall dimensions exceeding those of blanks by some 5-10 mm.

EFFECT: notably decreased deformation of blanks.

1 tbl

FIELD: metallurgy.

SUBSTANCE: method includes homogenisation of a bar, heating to 360-450°C, hot rolling, cold rolling with extent of deformation of 45-70% and intermediate annealing, and final thermal treatment, including three-stage artificial ageing according to the following mode: first stage at 80-125°C for 8- 24 hr, second stage at 130-180°C for 4-30 hr and third stage at 145-180°C for 2-18 hr or double-stage ageing, including the first and second, or the second or third, or the first or third stages.

EFFECT: application of the proposed technology will make it possible to produce rolled semi-finished products with improved operating properties, due to production of a fine-grain recrystallised structure and isotropy of properties.

3 cl, 5 ex, 8 tbl, 1 dwg

FIELD: metallurgy.

SUBSTANCE: method includes homogenisation of a bar, heating to 360-450°C, hot rolling, cold rolling with extent of deformation of 45-70% and intermediate annealing, and final thermal treatment, including three-stage artificial ageing according to the following mode: first stage at 80-125°C for 8- 24 hr, second stage at 130-180°C for 4-30 hr and third stage at 145-180°C for 2-18 hr or double-stage ageing, including the first and second, or the second or third, or the first or third stages.

EFFECT: application of the proposed technology will make it possible to produce rolled semi-finished products with improved operating properties, due to production of a fine-grain recrystallised structure and isotropy of properties.

3 cl, 5 ex, 8 tbl, 1 dwg

FIELD: metallurgy.

SUBSTANCE: proposed composition contains the following substances, in wt %: zinc - 5.0-5.8, magnesium - 1.1-1.2, chromium - 0.2-0.3, copper - 0.1-0.4, titanium - 0.05-0.15, cerium - 0.005-0.05, samarium - 0.005-0.05, silicon - not over 0.3, iron - not over 0.3, zirconium - not over 0.005, aluminium making the rest. Method of making semis from said aluminium alloy comprises first thermal treatment at up to 480°C, cooling to room temperature, and second thermal treatment at up to 200°C.

EFFECT: higher strength, lower residual strain.

11 cl, 4 ex

FIELD: metallurgy.

SUBSTANCE: composite material contains copper, manganese, zirconium, iron, silicon and boron, and has a structure consisting of solid aluminium solution and phases uniformly distributed in it at their further ratio in solid solution, wt %: 6-15 B4C, 2-6 Al15(Fe,Mn)3Si2, 2-6 Al20Cu2Mn3, 0.4-0.8 Al3Zr.

EFFECT: increasing heat resistance of material to heating processes at sufficient level of mechanical properties.

2 cl, 1 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: magnesium-containing high-silica aluminium alloys intended for use as structural materials, including shapes, bars, sheets and forged pieces, are manufactured with the help of a technological process containing the following operations: ingot casting from the alloy by method of casting into a chill mould, preliminary heating of the ingot in order to disperse particles of eutectic phase of silicon, treatment in thermoplastic condition and thermal treatment in order to produce an item of final shape and with modified microstructure. Aluminium alloys contain, wt %: 0.2-2 of magnesium and 8-18 of silicon and have homogeneous and fine-grained microstructure, at the same time the aluminium matrix is homaxonic with the average size of grain, not exceeding 6 mcm, and particles of silicon and secondary phase are dispersed at the average size of particles not exceeding 5 mcm. Without addition of any modifiers they are produced with low costs by combination of casting into a chill mould with treatment in thermoplastic condition and thermal treatment.

EFFECT: high plasticity and relatively high strength.

8 cl, 13 dwg, 10 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: aluminium alloy contains the following components: from 4.5 to 6.5 wt % magnesium, from 1.0 to 3.0% wt % silicon, from 0.3 to 1.0% wt % manganese, from 0.02 to 0.3% wt % chromium, from 0.02 to 0.2% wt % titanium, from 0.02 to 0.2 wt % zirconium, from 0.0050 to 1.6% wt % of one or more rare-earth metals, max. 0.2% iron, and the rest is aluminium.

EFFECT: alloy has high strength properties and is intended for use in die casting and related methods.

8 cl, 1 tbl

FIELD: metallurgy.

SUBSTANCE: aluminium-based alloy contains the following, wt %: zinc - 6.35 - 8.0, magnesium - 0.5 - 2.5, copper - 0.8 -1.3, iron - 0.02 - 0.25, silicon - 0.01 - 0.20, zirconium - 0.07 - 0.20, manganese - 0.001 - 0.1, chrome - 0.001 - 0.05, titanium - 0.01 - 0.10, boron - 0.0002 -0.008, beryllium - 0.0001 - 0.05, at least one element from potassium, sodium, calcium group in quantity of 0.0001 - 0.01 each, aluminium is the rest; at total content of zinc, magnesium, copper within 8.5-11.0, and that of zirconium, manganese and chrome - within 0.1-0.35. Method involves loading and melting of charge components, flux treatment of molten metal, molten metal purification, further vacuum treatment of molten metal in mixer and casting of ingots; boron is added to molten metal in the form of Al-Ti-Be alloy which is distributed at least one hour before molten metal pouring to mixer along the whole surface area of mixer bottom; at that, mixer is pre-heated to temperature which is by 15-30°C more than molten metal temperature, and vacuum treatment of molten metal in mixer is performed at temperature of 695-720°C, during 45-90 minutes.

EFFECT: invention allows obtaining high-strength aluminium alloys with absence of primary intermetallic compounds, decreased content in them of non-metallic inclusions and dissolved gases, with stable properties and optimum size of grain on basis of standard furnace and process equipment.

2 cl, 3 tbl

FIELD: metallurgy.

SUBSTANCE: Invention relates to metallurgy and may be sued in producing strained semi-finished products from thermally non-hardenable welded aluminium-based alloys used as structural and semiconductor material, primarily, in aerospace and nuclear engineering. Aluminium-base alloy comprises the following components in wt %: magnesium - 1.8-2.4, scandium - 0.2-0.4, zirconium - 0,1-0.2, cerium - 0.0001-0.005, iron - 0.01-0.15, silicon - 0.01-0.1, aluminium making the rest. Note here that iron-to-silicon content ratio may not be less than unity.

EFFECT: higher strength and conductivity, hence, reduced weight.

2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: invention refers to deformed thermally hardened high-tensile aluminium alloys Al-Zn-Mg-Cu designed for fabrication of all kinds of deformed semi-finished products, including thin sheets used in aircraft and machine engineering and other branches of industry. Deformed alloy on base of aluminium and an item out of it contain the following components, wt %: zinc 2.5-4.0, magnesium 4.1-6.5, copper 0.2-1.0, iron to 0.25, silicon to 0.15, scandium 0.005-0.3, zirconium 0.005-0.25, nickel and/or cobalt to 0.1, titanium to 0.15, boron and/or carbon to 0.05, at least one element out of group: hafnium to 0.15, molybdenum to 0.15, cerium to 0.15, manganese to 0.5, chromium to 0.28, yttrium to 0.15, vanadium to 0.15, niobium to 0.15, aluminium and unavoidable impurities - the rest, also ratio of Mg contents to Zn contents is more or equal to 1.1.

EFFECT: production of alloy and items out of it possessing raised strength properties at simultaneous increased wear-resistance, reduced rate of crack growth, increased durability of welded connections and reduced density, which results in increased resource and reliability of items operation and in reduced weight of structures.

3 cl, 2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: alloy contains following components, wt %: magnesium 4.1-4.9, titanium 0.01-0.04, beryllium 0.0001-0.005, zirconium 0.05-0.12, scandium 0.17-0.30, cerium 0.0001-0.0009, manganese 0.19-0.35, chromium 0.01-0.05, group of elements, containing iron and silicon 0.06-0.25, aluminium is the rest, at that value of iron content relation to silicon content has to be not less than unity.

EFFECT: increased strength property, strength of welded connection at cryogenic temperatures, weight saving of welded fabrication, manufactured from suggested alloy.

2 tbl, 1 ex

FIELD: metallurgy; alloys.

SUBSTANCE: alloy and products out of this alloy contain the following elements, mas.% magnesium 0.6-1.2; silicon 0.6-1.2; manganese 0.3-1.0; iron 0.1-0.5; copper 0.05-1.0; titanium 0.005-0.05; at least one element out of the group: tin 0.6-1.0; bismuth 0.2-0.8; at least one element of the group: gallium 0.001-0.05; calcium 0.001-0.05; at least one element from the group: boron 0.0005-0.005; carbon 0.0001-0.005; aluminium - the rest.

EFFECT: there obtained an alloy and products out of it not containing lead and possessing upgraded machinability, high corrosion resistance and strength.

2 cl, 4 dwg, 2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: said utility invention relates to the manufacture of products of a rolled aluminium alloy highly resistant to damage. The method involves casting an ingot with a chemical composition selected from the group consisting of AA2000, AA5000, AA6000, and AA7000 alloys, homogenisation and/or heating of the ingot after casting, hot rolling of the ingot into a hot-rolled product and, optionally, cold rolling of the hot-rolled product into a cold-rolled product. After the hot rolling, the hot-rolled product is cooled from the hot-rolling mill output temperature (Tout) to 150°C or lower, at a controlled cooling rate decreasing within the set range according to a continuous cooling curve determined using the following expression: T(t)=50-(50-Tout)eα-t, where T(t) is the cooling temperature (°C) as a function of the cooling time (hours), t is the cooling time (hours), and α is a parameter determining the cooling rate, within a range of -0.09±0.05 (hr-1).

EFFECT: enhanced impact strength; resistance to growth of fatigue cracks, and corrosion resistance without strength deterioration.

19 cl, 7 tbl, 1 dwg, 2 ex

FIELD: nonferrous metallurgy.

SUBSTANCE: invention is intended for use in metallurgy, mechanical engineering, and aircraft industry, in particular for manufacturing honeycomb structures. Alloy is composed of, wt %: magnesium 8-10, manganese 0.1-0.15, zirconium 0.15-0.2, cobalt 0.05-0.2, boron 0.005-0.007, beryllium 0.001-0.02, iron 0.15-0.2, silicon 0.15-0.2, titanium 0.1-0.2, aluminum - the balance. Ingot for manufacturing structural foil is obtained by semicontinuous casting in rotary crystallizer at volumetric cooling 4-20°C/sec. Structural foil manufacturing process comprises homogenization, hot rolling, annealing, cold rolling followed by annealing in air atmosphere, second cold rolling followed by annealing, and final cold rolling.

EFFECT: increased strength of alloy at ambient and elevated temperatures and improved processability un rolling stage.

3 cl, 3 tbl

FIELD: alloy metallurgy.

SUBSTANCE: invention relates to deformable, thermally strengthened, highly technologically effective, corrosion-resistant welding alloys based on the system Al-Mg-Si and articles made of thereof. The proposed alloy and article made of thereof comprise the following components, wt.-%: magnesium, 0.3-1.2; silicon, 0.3-1.7; manganese, 0.15-1.1; calcium, 0.05-0.; sodium, 0.0002-0.01, and at least one metal taken among the group comprising copper, iron, zirconium and chrome, 0.02-1.0, and aluminum, the balance. Invention provides the development of deformable alloy based on the system Al-Mg-Si and article made of this alloy that show enhanced technological effectiveness at cold stampings by extrusion and improved workability by cutting.

EFFECT: improved and valuable properties of alloy and article.

3 cl, 3 tbl, 1 ex

Up!