Preparation for a gun barrel, a method of manufacturing gun barrels and gun barrel
The invention relates to a method of manufacturing gun barrels and can be used for manufacturing of all types of firearms. Proposed procurement for gun barrels, consisting of a steel rod, made of at least two kinds of steel, at least one of which is a powder steel, with a rod subjected to repeated twisting around its longitudinal axis during one or more stages of hot processing. The torsion rod perform primarily to the elevation angle of the helical line 45-90and then drill or punch along its longitudinal axis. The technical result is to increase strength properties. 3 S. and 7 C.p. f-crystals, 3 ill.The invention relates to a preparation for a gun barrel, while the preform consists of a rod of metal. The invention relates also to a method of manufacturing gun barrels and gun barrel. The concept of the gun barrel also includes gun barrels. The invention is applicable to all types of firearms, such as manual, semi-automatic or automatic small arms, cannons, etc. but initially razrabatyvalis is automatic and semi-automatic rifles, guns and so on, are usually manufactured from blanks, which consists of a rolled steel rod or forged bar material for formation of the channel bar material rastaivaya.One of the important aspects related to the production of gun barrels, is a strength, especially when the gun fires. So the gun barrel must be of sufficient wall thickness so that they could withstand a tensile strength that appears when the shot a certain charge. The required wall thickness can lead to heavier weapons, which will be expensive and/or inconvenient to use.One of the obstacles in the famous gun barrels is that they are made from bar stock material, which after rolling/forging exerts its better mechanical properties in the longitudinal direction of the rod. Usually fatigue strength, the number of cuts and ductility in the longitudinal direction by 20-50% higher than in the transverse direction. This is mainly due to the orientation of non-metallic occlusion and cracking because of it. During the manufacture of rod-shaped material significantly extend in the longitudinal napravleniyaner significantly more compared to the longitudinal direction, thus the fatigue strength, the magnitude of the grooves and ductility in the transverse direction will be less compared to the longitudinal direction.When using a rifle barrel, i.e., when performing shooting out of the barrel, gun barrel having the tensile stresses from being set up in the trunk of the internal excess pressure, which can reach values of 3500 bar (350 MPa). Therefore, the stress distribution will fundamentally the same as in the cylindrical boiler, with the only difference that the stresses in the longitudinal direction perceive arms shutter and bullet or shot. In the barrel in the longitudinal direction will not have a significant voltage, but, on the other hand, in the tangential direction around the trunk of the tensile stresses will be larger. Therefore, the main disadvantage of the known gun barrels is that they exhibit a weaker mechanical properties in the transverse/tangential direction than in the longitudinal direction.The problem is compounded by the fact that on the technical side, there is a need to increase the charge in firearms while simultaneously desirable reduction in weight.Another disadvantage, which refers to izvestnymi wear or slight stiffness in the channel, taking into account the decision of some countries on the replacement of certain types of hunting lead shot to steel.In accordance with the present invention minimize these problems by using blanks for gun barrels, obtained according to the proposed method. The invention also offered a gun barrel for a firearm made from billet proposed in this invention.Thus, in accordance with the first aspect of the present invention proposed procurement for gun barrels, consisting of a steel rod, made of at least two kinds of steel, at least one of which is a powder steel, with a rod subjected to repeated twisting around its longitudinal axis, preferably in one or more stages of hot processing.The specified rod may be subjected to twisting around its longitudinal axis by the angle/elevation angle of the helical line of 45 - 90preferably 60-88more preferably 75-87. Twisting can be performed automatically or manually. When twisting according istorie to curl were mainly oriented in the longitudinal direction of the rod, to a greater extent will be mainly oriented tangentially relative to the rod, mainly on the periphery. Therefore, occlusion does not create a threat of occurrence of cracks at the tangential tensile stresses that occur during firing of the weapon barrel made from a rod, as compared with the case where they are oriented in the longitudinal direction of the rod. Strength and fatigue limit of the rod increased in the tangential or transverse directions, when the rod is subjected to twisting according to the invention. The fact that the orientation of the occlusion will be the most tangential to the periphery, is an advantage, because the tensile stress maximum.The tensile strength of the rod in the gap can be increased after twisting according to the invention is approximately 1-5%, plasticity (shrinkage) can be increased by about 20-550%, the value of the grooves can be increased by approximately 20-300% and the fatigue strength can be increased to approximately 30-50%; these values are related to growth in the transverse direction and to traditional steels heat treatment for gun barrels of the shotguns.The tensile strength of the rod tensile and yield strength could critique the key steel to increase the hardness and strength without to the resulting material showed a tendency to brittleness, because the twisting gives a viscosity increase. Alternatively, you can choose a more rigid and durable alloy. This increase in strength will lead to improved resistance to wear and therefore can also be used to save weight due to reduced wall thickness in manufactured gun barrels.Moreover, in General it is true that the steel will become more viscous and solid as increasing the degree of processing. When twisting according to the invention can increase the degree of plastic deformation without changing the dimensions of the rod. The direction of the mechanical processing is also carried out in the most advantageous direction, i.e. in the direction in which will be the most powerful load during use of the weapon.As raw material for the rod, you can use any steel or steel alloys suitable for gun barrels. From the point of view of strength is particularly advantageous to use a powder metallurgical alloy, preferably quick-hardening powder metallurgical alloy. These types of alloys are today common in special tools for machining metals due and the flax powder metallurgy, preferably from powder steel.Powder metallurgy also provides an opportunity to get mixed materials, which are suitable for this purpose. As the material for the part, which should form the inside channel of the gun barrel, you can choose accordingly hard and wear-resistant material with high resistance to friction of the bullet or projectile, but which provides good resistance to corrosion caused by the powder gases, powder spray and moisture, which may contain dissolved gases and powder spray. As the material intended for the formation of the external part of the gun barrel, instead, it is preferable to choose a material with high toughness and strength. Thus, the rod can be made of a composite material containing the first wear-resistant steel, located in the core rod, and a second, solid steel, located outside the Central part and/or in the peripheral region of the rod.In addition, the gun barrel can buy decorative appearance along with achievement of the useful properties of the steel material, thanks to the use of so-called Damascene technique patterned and the receiving of powder metallurgy, which is preferable, is described in SE-C-9400127-8.In the Damascene technique, patterned inlays using powder metallurgy using at least two different steel material having essentially different alloy compositions, for example, two substantially different types of stainless steel, with at least one of them consists of a powder. These two steel material is incorporated in the consolidated (sealed) body, for example, by hot isostatic pressing, the so-called GUI (HIP), under pressure of over 600 bar (60 MPa) and at temperatures above 1000C. Other possible technologies seals are formed by extrusion and gradual forging of powder in the capsule. If necessary, use a powder that is produced by the method of so-called atomization, which means that the flow of molten metal is divided into small drops by means of inert gas, after which it drops is allowed to harden in the inert gas in the form of a powder. After that, the powder is sieved to a particle size of no more than 1 mm, the ISU can make traditional hot isostatic pressing, with two steel material, which must be objetos pumped the air and which is subjected to hot isostatic pressing. The capsule may traditionally reserved for powder metallurgy, consist of plates, such as plates, carbon steel, but can also be foreseen that the capsule is at least partially comprised of stainless steel, which will become an integral part of the final product. In addition, you can use capsules of non-metallic materials such as glass, enamel, etc.Possible production line is a production of powder by the method of so-called atomization, the placement of two or more kinds of powder, preferably on a pre-selected drawings, in capsule, preferably in a steel capsule, compaction to full density by hot isostatic pressing, extrusion molding or forging compacted body and the subsequent continuous machining pressure in the rod, twisting according to the invention during a stage of thermal treatment and etching in acid to achieve a decorative effect.In order to obtain a decorative effect, choose a steel material have different compositions, so that after etching to obtain the desired contrast effect. For example, if both materials are stainless steel, one of Neri limited resistance to corrosion and which accordingly can be easily subjected to etching and blacking acid, while other stainless steel consisting of, respectively, more resistant to corrosion of low-carbon stainless steel with less ability to etching than the martensite (vysokokonsolidirovannoj stainless steel), for example, austenite, ferrite or ferrite-austenitic stainless steel, or perhaps martenitsa stainless steel, have a significantly lower carbon content than said first stainless steel. In principle according to the invention can also use stainless steel two varieties of the same type, such as martensite, which has the same composition, except that one of the steels, but not the other, fused with one or more substances or contains a much larger quantity of that substance or those substances, such as phosphorus, resulting in the steel becomes much more potreblyaemoi than the other steel, all this in order to achieve the desired contrast effect.Thus, the steel rod, which is a preparation for a gun barrel may be made of at least two types of steels of different chemical composition, treated with obtaining a compressed body, with subsequent plastic and etching the surface of the workpiece or gun barrels can be obtained a decorative pattern.According to the invention different steel materials can be stacked in layers, for example as described in SE-C-9400127-8. It is therefore particularly preferably the same as in the above-described technique of mixing, put wear or solid steel material as a homogeneous core along the longitudinal axis of the rod and layers of two or more steel materials around this core, while the outer steel materials demonstrate mainly strength. Thus, in preparation for a weapon barrel first, wear-resistant steel can be located in the core rod, and a second, solid steel in areas outside the Central part and/or in the peripheral region of the rod, the blank further comprises a third type of steel, while the second steel is preferably alternately with the third steel or with the first steel, and at least the second and third (or first) steel is selected so that when the etching on the surface of the workpiece or gun barrels can be obtained a decorative pattern. Also envisaged to stack layers of different steel materials in the form of more or less concentric rings. Moreover, different steel materials can be laid Rel the steel material. Different steel materials can be chosen for each particular case, to give desirable properties, including strength, durability, hardness, viscosity, etc. in different areas of the rod.With regard to the use of the Damascene technique, the torsion rod, which is designed to create blanks for gun barrels, will lead to additional length of the surface of the gun barrel. Accordingly, it is possible to make gun barrels, for example with a spiral pattern on the surface or by a combination of random or selected pattern and a spiral pattern.The invention also offers a method for the production of gun barrels of steel rod, wherein the rod is made of at least two kinds of steel, at least one of which is a powdered steel, after which the rod is twisted around its longitudinal axis during one or more stages of hot processing, mainly to the elevation angle of the helical line 45-90preferably 60-88more preferably 75-87and then drill or punch along its longitudinal axis.In the proposed method can realize the hot processing material of the rod is subjected to at least partial recrystallization. Alternatively, the twisting can be accomplished in one stage, if performed slowly. The purpose of twisting in several stages or slow conduction in one stage is the elimination of local overheating, which can occur in certain cases when twisting perform during one of the fast stage. Such local overheating can cause surface defects in the rod, which with continued twisting can develop into cracks on the surface. For continuous twisting cracks will grow even more, because of which the rod is twisted. The different grades of steel the critical limit for the appearance of surface defects is changed.When using the present invention was created the opportunity to increase the charge of firearms and/or reduce the weight of the weapon, because the weapon barrel can be wall smaller thickness in comparison with the known weapons trunks.The effect of increasing the mechanical properties, which can be achieved are presented below and is considered as an example with reference to the accompanying drawings, in which Fig.1 shows how many turns you need to tighten a 30 mm round rod to get data is the processing, achieved by curl.The example refers to the 30-mm round rod, made of steel, hot working, traditional for the manufacture of barrels of shotguns. In Fig.1 shows how many turns per 1 m is required when twisting to get the desired angle/elevation angle. In Fig.2 shows the growth plasticity in the tangential direction as a function of elevation angle. It is expected that other parameters of mechanical properties are increased in the same way, but in different proportions compared to the above. In Fig.3 shows degree of processing as measured by the percentage of the tangential elongation along the perimeter of the rod, which is achieved by bending, as a function of elevation angle. This increased degree of processing leads to additional lengthening of the occlusion and, thus, to further improve the mechanical properties.In Fig.2 and 3 shows that a significant extension and improvement of mechanical properties is achieved when the angle of ascent 45but further increase of the angle of elevation gives even better results. At an angle of up to 85the material stretches around the perimeter of 1000%. This means that a 30-mm diameter rod, which twisted 85% managing 10-mm rod.The invention is not limited to the above-described variants of implementation and may vary within the scope of the claims.
Claims1. Preparation for a gun barrel, consisting of a steel rod, wherein the rod is made of at least two kinds of steel, at least one of which is a powder steel, with a rod subjected to repeated twisting around its longitudinal axis during one or more stages of hot processing.2. Procurement under item 1, characterized in that the rod is subjected to twisting around its longitudinal axis until the angle helix 45-90preferably 60-88even more preferably 75-87.3. Procurement under item 1 or 2, characterized in that the rod is made by powder metallurgy, preferably from powder steel.4. The workpiece according to any one of paragraphs.1-3, characterized in that the rod is made of a composite material containing the first wear-resistant steel, located in the core rod, and a second, durable, steel, located outside the Central part and/or in the peripheral region of the rod.5. Serotoninergicheskogo composition, processed to obtain a compacted body, followed by plastic deformation to obtain a rod, and two types of steel with different chemical composition are selected so that, when etching the surface of the workpiece or gun barrels can be obtained a decorative pattern.6. Procurement under item 5, wherein the first wear resistant steel is located in the core rod, and a second, solid steel is located outside the Central part and/or in the peripheral region of the rod, the blank further comprises a third type of steel, the second steel is preferably alternately with the third steel or with the first steel, and at least the second and third (or first) steel is selected so that when the etching on the surface of the workpiece or gun barrels can be obtained a decorative pattern.7. Method for the production of gun barrels of steel rod, wherein the rod is made of at least two kinds of steel, at least one of which is a powdered steel, after which the rod is twisted around its longitudinal axis during one or more stages of hot processing, mainly to the elevation angle of the helical line 45-90176.gif">and then drill or punch along its longitudinal axis.8. The method according to p. 7, wherein implementing at least two-stage thermal treatment, during which the rod is twisted, while between stages hot working the rod material is subjected to at least partial recrystallization.9. The method according to p. 7, characterized in that the twisting is carried out in a single stage hot working, while twisting exercise slowly to eliminate local overheating.10. Gun barrel for firearms, characterized in that it is made from a blank according to any one of paragraphs.1-5.
FIELD: powder metallurgy, namely processes for hot pressing of envelopes.
SUBSTANCE: method for making envelopes of powders of refractory materials comprises steps of preparing blank of composition "powder-organic binder" by rolling powder to sheet blank; cutting out several different diameter discs of prepared sheet; cutting out sectors in each disc; placing formed discs into press-mold while abutting cut lines of discs; placing releasing means between mutually contacting surfaces of blank and press-mold; then performing hot pressing at softening temperature of organic binder.
EFFECT: enhanced factor of material usage, lowered density difference of envelopes.
3 cl, 1 ex
FIELD: powder metallurgy, manufacture of complex-profile hard-alloy articles with inner cavities, for example ball plugs for cocks.
SUBSTANCE: method comprises steps of placing powder of titanium carbide in shell mold of refractory ceramic material non-wetting with impregnating metal; performing vibration compaction for making mold piece; fixing mold piece by means of upper lid of refractory ceramic material having through openings; placing on said lid piece of impregnating metal whose size exceeds that of lid openings; performing infiltration of mold piece by melt metal due to heating it till temperature higher than liquidus point of metal.
EFFECT: simplified manufacturing process for making hard-alloy articles of high hardness.
2 cl, 2 dwg, 1 tbl, 2 ex
FIELD: powder metallurgy, namely methods for making cutting tool of carbide powders with inner ducts for cooling liquid.
SUBSTANCE: method for forming powder blank of metal cutting tool having opening, at least one recess and at least one passage connecting said opening at least with one recess comprises steps of placing in die upper punch with front end having at least one first protruding member; lower punch having front end and at least one second protruding member; pouring metal powder between them. Pressing is realized due to motion of upper and lower punches one to other until one first protruding member touches at least one second protruding member at least in one zone. Opening is restricted by space where at least one second protruding member is arranged between upper and lower punches. At least one passage is formed at least in one portion of contour.
EFFECT: shortened time period of manufacturing process.
9 cl, 3 dwg