DE102013100930B3 - Manufacturing cartridge case, comprises e.g. providing first- and second workpiece parts, two-dimensionally joining two workpiece parts, and forming workpiece produced from two joined workpiece parts to produce cylindrical sleeve - Google Patents

Abstract

Manufacturing cartridge case, comprises e.g. (a1) providing a first workpiece part (37) made of a metal, comprising a first material which is formed by an aluminum alloy that is free of a copper component, and exhibits a first joining surface (39), (b1) providing a second workpiece part (38) made of a metal, comprising a second material having a second joining surface (40), (c1) two-dimensionally joining two workpiece parts with their joining surfaces, and (d1) forming a workpiece produced from the two joined workpiece parts, to obtain the cartridge case, and to produce a cylindrical sleeve. Manufacturing cartridge case, comprises (a1) providing a first workpiece part (37) made of a metal, comprising a first material which is formed by an aluminum alloy that is free of a copper component, and exhibits a first joining surface (39), (b1) providing a second workpiece part (38) made of a metal, comprising a second material having a second joining surface (40), (c1) two-dimensionally joining the two workpiece parts with their joining surfaces, and (d1) forming a workpiece produced from the two joined workpiece parts, to obtain the cartridge case, and to produce a cylindrical sleeve having a shell section made of the first material and a bottom section made of the second material, whose open end section is reduced in diameter by forming without prior heat supply; or (a2) providing a casting mold having two mold sections separated by a movable separating wall, (b2) filling a liquefied first material which is formed by an aluminum alloy that is free of a copper component, and comprises a metal, in one of the mold sections, (c2) filling a liquefied second material comprising a metal, into other mold section, (d2) removing the separating wall for solidifying the two materials and two-dimensional joining of the two materials such that a workpiece made of two interconnected workpiece parts is formed, (e2) removing the workpiece from the casting mold, and (f2) forming the workpiece to obtain the cartridge case, and to produce a cylindrical sleeve having a shell section made of the first material and a bottom section made of the second material, whose open end section is reduced in diameter by forming without prior heat supply. The second material exhibits a hardness which is greater than the hardness of the first material. A metal oxide layer (41) which is respectively present on the joining surfaces is removed or the metal oxide layers which are respectively present on the joining surfaces are connected to an intermediate layer, before or during the joining of the two workpiece parts. The second liquefied material exhibits a hardness which is greater than the hardness of the first liquefied material, when the two materials are completely solidified and cooled.

Description

The present invention relates to a method for producing a cartridge case.

In general, cartridge cases are made of a material with sufficient strength so that the cartridge case does not tear when igniting the charge and jammed in the chamber. Often cartridge cases are made of brass. Brass has the disadvantage that the cartridges are very heavy. Especially with the loading of vehicles or aircraft, this weight is disadvantageous.

Attempts have been made for a long time to produce cartridge casings of a lighter material, for example of aluminum. However, it has been shown at an early stage that aluminum cartridge cases do not easily withstand the stresses during firing. Therefore, for example, in CH 503 966 A proposed to use a special alloy of aluminum, copper, magnesium and silicon. However, it is disadvantageous that a heat treatment must be carried out before the sleeve can be reduced at its open end by pulling in the diameter. That's why production takes a lot of time and is relatively expensive.

Apart from attempts to change the alloy constituents of an aluminum alloy in order to obtain a light yet sufficiently stable cartridge case, other development approaches are also to be pursued. For example, beats DE 1 007 215 A to use a pulled out of aluminum sleeve in another, pushed over plastic sleeve. This is intended to prevent tearing of the aluminum during the shot through the elastic plastic.

A cartridge case made of aluminum is also made DE 75 823 known. There, the bottom of the cartridge case is provided with a jacket or insert of a stronger material such as steel or brass.

To achieve sufficient stability of a cartridge case with an aluminum jacket suggests DE 21 36 77 A to make the bottom piece from a separate part and to connect form-fitting with the jacket made of aluminum. The two parts are positively connected with each other. DE 24 39 99 A describes a cartridge case in which a cup-shaped bottom is made of nickel, in which subsequently a jacket of the cartridge case forming aluminum sleeve is used. By pressure and heat, the two parts are connected. In these methods, the two parts must be made separately and then joined together.

Out DE 23 69 70 A is known a cartridge case, in which a plated sheet is used as the starting material for the production. In this case, a coating of aluminum or an aluminum alloy is applied to a thin steel sheet. During subsequent reshaping, care is taken to ensure that the aluminum coating is on the outside to protect the cartridge case from corrosion. The cartridge case thus has a full stainless steel sheath to protect the steel.

Out DE 700 255 A It is known to use two different aluminum alloys for producing a cartridge case.

DE 29 09 267 C3 generally describes a friction welding machine, which should have a small footprint.

A forming machine with a welding unit is in DE 103 02 458 B4 known. The welding process is performed to avoid hot cracks on a warmed workpiece.

DD 109 538 B1 relates to a method for producing composite materials, in particular composite cast blocks. For this purpose, different liquefied materials are poured into a common mold and separated by a separating body. During curing, mixing of the liquid materials - apart from a narrow transition zone - is prevented by the separating body.

The production of a cartridge case of two different, metal-containing materials is known, but consuming. It has been shown that, for example, the superimposition of two blanks made of different materials and the subsequent forming in a press does not ensure a sufficient connection between the two materials. The known from the prior art method in which initially two cartridge sleeve parts are prepared and then joined together, are time consuming and expensive and therefore unsuitable for mass production.

Starting from the known prior art, it can therefore be regarded as an object of the invention to provide a cost-effective method for the production of lightweight cartridge cases, which have a sufficient strength.

This object is achieved by a method having the features of claim 1 and a method having the features of claim 7.

For producing the cartridge case, in a first method according to the invention a first workpiece part made of a first material containing metal and a second workpiece part made of a second material containing metal are provided. The two materials may each be an aluminum alloy in one embodiment. The hardness or strength of the second material is greater than that of the first material, which can be effected by different processing methods or alloying components. Each of the workpiece parts has a joining surface, wherein the two workpiece parts are connected flat at their joining surfaces. After two-dimensional joining of the two workpiece parts, a workpiece is produced, which is subsequently shaped in a press to form the cartridge case. Preferably, the forming of the workpiece is carried out by extrusion. This results in a cartridge case, the closed bottom portion of the second material of the second workpiece part and the shell portion consists essentially of the first material of the first workpiece part. An overlap area may exist between the bottom portion and the skirt portion by having both materials present.

Important in the joining of the two workpiece parts is the elimination of the metal oxide layer, which is present on the joining surfaces. If aluminum alloys are used for the two materials, the metal oxide layer is an aluminum oxide layer. Such an oxide layer prevents a sufficiently strong connection, which in the subsequent forming leads to the fact that the cartridge case in the transition region between the two materials has weak points at which the cartridge case can break or break when the charge ignites.

In order to avoid this problem, it is provided in a method according to the invention to remove the metal oxide layers on the joining surfaces before or during the connection of the two workpiece parts with one another. As a result, a surface secure connection between the two materials or between the two workpiece parts is achieved, so that no weaknesses arise during forming of the workpiece. The cartridge case thus produced has in the bottom portion of a sufficiently high strength, which withstands the charges when igniting the charge. In addition, the weight of the cartridge case is reduced. By connecting the two materials or workpiece parts to a workpiece before forming the forming press can work with high stroke rates and it is an efficient and inexpensive method for producing the cartridge case achieved.

For removing the metal oxide layer in the first process according to the invention, there are various possibilities, depending on the bonding method used:
For example, the metal oxide layer can be removed by pickling, by heat or laser treatment and the two workpiece parts are then connected to one another by plating, in particular roll-plating. This method is particularly suitable for total thickness of the workpiece of up to about 3 mm. As far as can be made of such a workpiece cartridge cases with a small caliber.

Alternatively, the metal oxide layer can be rendered harmless, as it were, by using a solder or bonding material as an intermediate in plating or roll cladding. As an intermediate layer, a material is used for plating or roll cladding which has a higher oxygen affinity than the metal of the first and second material. As a result, in spite of the existing metal oxide layer, a stable and solid surface connection between the two workpiece parts can be achieved. For example, a copper-based material is suitable as a material for the intermediate layer when the first and / or the second material contains aluminum.

It is also possible to connect the two workpiece parts by pulsed magnetic welding. In particular, the joining surface is formed on a workpiece such that it does not run parallel to the joining surface of the other workpiece part. Rather, the one joining surface, starting from all side edges, rises to a projecting point in a central region of the joining surface. For example, the relevant workpiece part in the region of the joining surface have a conical, a pyramidal, a frusto-conical or a truncated pyramidal shape. When juxtaposed, therefore, form around the protruding point a wedge-shaped gap. Due to the magnetic field in pulsed magnetic welding, the two joining surfaces are applied at high speed starting from this projecting point to each other, wherein the metal oxide present on the two joining surfaces is discharged in all directions from the gap and eject so to speak laterally. It creates a solid weld.

It is also possible to connect the two workpiece parts by friction welding. The two joining surfaces are preferably configured as flat surfaces. Due to the relative rotation of the two joining surfaces against each other during the friction welding, the metal oxide layer is removed and the metal oxide discharged radially outward, so that here too a solid Connection between the two workpiece parts is created.

It is also possible to connect the two workpiece parts by capacitor discharge welding. In particular, a projection or an elevation is present at the joining surface of a workpiece part. At the survey, the two joining surfaces abut each other. In addition to the survey, there is initially a gap between the two joining surfaces. By discharging the capacitor in the capacitor discharge welding a particularly high current density is achieved at the survey. The material liquefies and creates a kind of plasma cloud, which expands outwards in the gap and removes the metal oxide layers on the joint surfaces.

In a second method according to the invention, the workpiece, which consists of the first material and the second material, is produced by casting in a casting mold. The casting mold has two mold sections separated from each other by a movable partition wall. The liquefied first or second material is filled into the respective associated mold section. The gradual or continuous slow withdrawal of the partition during solidification of the two materials, the two materials are connected flat. This process can be carried out in the absence of oxygen, so that no metal oxide layer can form in the joining region of the two materials and thus a firm connection between the two materials is produced during the production of the workpiece by the casting.

In both methods according to the invention, the first material is formed by an aluminum alloy containing no copper. As a result, the shell portion of the cartridge case can be deformed without heat treatment, for example, to collect the end portion in the region of the open end of the cartridge case. As a second material, for example, aluminum, brass or steel may be used or an alloy having at least one of these constituents.

Since a heat or annealing treatment of the cartridge case is avoided, embrittlement of the first material at the bottom portion - including at the edge of the cartridge case bottom - avoided because the überetektische silicon is not deposited at the grain boundaries. As a result, there is no risk that the cartridge case breaks when pulling out of the chamber after delivery of the shot.

Preferably, the thickness of the layer of the first material is greater than the thickness of the layer of the second material of the workpiece produced for forming. For example, the thickness of the layer of the first material 12 to 14 mm and the thickness of the layer of the second material 6 to 8 mm.

When forming the workpiece for producing the cartridge case, a cylindrical sleeve is first produced, for example by a one-stage or multi-stage extrusion process. Subsequently, the diameter of the end portion is reduced with the open end of the cylindrical sleeve, the sleeve is thus retracted in the end portion. This retraction takes place in particular without prior heat. After retraction, the cartridge case is cut to length by a separation process to the desired length. Before or after drawing in, the bottom section is reshaped. In this case, for example, a ignition hole and / or an ejector groove can be produced.

In all of these connection methods, a stable connection between the two workpiece parts can be achieved very cost-effectively before forming. The forming itself can be done with high stroke rates.

Advantageous embodiments of the invention will become apparent from the dependent claims and the description. The description is limited to essential features of the invention. The drawing is to be used as a supplement. Hereinafter, embodiments of the invention will be explained in detail with reference to the drawing. Show it:

1 a schematic representation of an embodiment of two workpiece parts in a side view,

2 a schematic representation of an embodiment of a workpiece in a side view,

3 a schematic representation of another embodiment of a workpiece in side view,

4 a schematic of an embodiment for connecting two workpiece parts by roll cladding,

5 a schematic representation of a modified embodiment for connecting the two workpiece parts by roll cladding,

6 a schematic representation of an embodiment for connecting the two workpiece parts by capacitor discharge welding,

7 a schematic representation of an embodiment for connecting the two workpiece parts by pulse magnetic welding,

8th a schematic representation of an embodiment for connecting the two workpiece parts by friction welding,

9 a schematic representation of the production of the workpiece from two different materials by casting and

10a to 10h each a schematic representation of a stage for the forming of the workpiece to the cartridge case.

The invention relates to a method for producing a cartridge case 20 as they are in 10h is shown schematically. The cartridge case 20 has a bottom section 21 on, on which the cartridge case 20 closed is. At the bottom section 21 closes a shell section 22 at. In this coat section 22 is the cartridge case 20 at least partially hollow cylindrical or conical and has a cavity 23 for receiving a propellant charge on. At the bottom of the section 21 opposite open end 24 is the cartridge case 20 to the cavity 23 open.

By means of the method according to the invention, a lightweight yet sufficiently stable cartridge case is intended 20 getting produced. To achieve this, there is the cartridge case 20 made of two different materials. Both materials contain or consist of metal. A first material W1 is formed in the embodiment of a copper-free aluminum alloy. A second material W2 has a greater hardness than the first material W1 and is also formed in the exemplary embodiment by a comparison with the aluminum alloy of the first material W1 harder aluminum alloy. Alternatively, the second material W2 could also be brass or steel or an alloy of one of these components.

These two materials W1, W2 become a workpiece 25 produced. The workpiece 25 serves as starting material for the forming. From the workpiece 25 becomes by deformation the cartridge case 20 made, as later with reference to the 10a to 10h will be explained.

The workpiece 25 can be made in different ways. In 9 is a first embodiment of a manufacturing method for producing the workpiece 25 illustrated. It becomes a mold 30 with two through a movable partition 31 separate mold sections 32 . 33 provided. The mold sections 32 . 33 form a cavity in the mold 30 , the shape of the workpiece to be produced 25 equivalent. In 9 this is illustrated only in a very schematic way.

In the one shape section 32 becomes liquefied first material W1 and in the other form section 33 liquefied second material W2 filled. During the solidification process, the dividing wall becomes 31 gradually from the mold 30 withdrawn, so that the still flowable materials W1, W2 come into direct contact with each other and establish a connection with each other. This process can take place in the absence of an oxygen atmosphere, so that no metal oxide layer and, in the exemplary embodiment, no aluminum oxide layer can form on the joining surface between the first material W1 and the second material W2.

It is also possible on movable walls or wall sections of the mold 30 apply a compressive force F, so that the flowable materials W1, W2 when pulling out the partition 31 additional available volumes within the mold 30 without formation of cavities in the workpiece produced 25 fill at the joint.

It thus becomes a workpiece 25 made as it is in 2 schematically illustrated in side view. The two materials W1, W2 abut each other directly at a joint. The workpiece 25 thus has a layered structure and consists of a first workpiece part 37 from the first workpiece material W1 and a second workpiece part 38 from the second material W2. The two workpiece parts 37 . 38 may in particular have a circular peripheral shape. The workpiece 25 preferably has a cylindrical shape. The thickness D1 of the first workpiece part 37 may be different and in particular greater than the thickness D2 of the second workpiece part 38 , The thickness D2 of the second workpiece part 38 corresponds essentially to the thickness of the bottom section 21 the cartridge case to be produced 20 , The thickness D1 of the first workpiece part 37 depends on the length of the jacket section 22 the cartridge case 20 specified.

For the production of the workpiece 25 there is next to the basis of 9 described pouring also other possibilities. Here are the two workpiece parts 37 . 38 in particular separately provided and connected by a joining process surface. For connection, the first workpiece part 37 a first joining surface 39 and the second workpiece part 38 a second joining surface 40 on. By connecting the two workpiece parts 37 . 38 on their wings 39 . 40 becomes the workpiece 25 produced. It can be the circular Peripheral shape before the joining process already at the two workpiece parts 37 . 38 be present or produced or the circular Umfrangsform for the workpiece 25 Alternatively, after the joining of sheet-metal or band-shaped workpiece parts 37 . 38 by a separation process, such as cutting or punching, are obtained.

When connecting the two workpiece parts 37 . 38 there is a problem that affects the joining surfaces 39 . 40 a metal oxide layer 41 and, according to the example forms an aluminum oxide layer, the stable connection of the two workpiece parts 37 . 38 prevented or at least impeded each other. This may result in later forming of the workpiece 25 to the cartridge case 20 weak points or connection defects between both materials W1, W2 come. This in turn causes the cartridge case 20 when firing the propellant charge tear or break and jam in the chamber.

By way of example, it is therefore proposed to use the metal oxide layer 41 before or when connecting the two workpiece parts 37 . 38 to remove or render harmless. Based on 4 to 8th For this purpose, different joining methods are explained, with workpieces 25 according to 2 or 3 arise.

In an embodiment according to the 4 and 5 become two band-shaped or sheet-shaped workpiece parts 37 . 38 by plating and, for example, joined together by roll-plating. In the first embodiment according to 4 For this purpose, the metal oxide layer is removed by pickling, by heat or using a laser prior to roll-plating. As a result, then, during the roll cladding, a good connection to the joining surfaces 39 . 40 be achieved. It arises after joining and leaving a workpiece 25 according to 2 ,

Alternatively, the metal oxide layer 41 on the workpiece parts 37 . 38 remain and an intermediate layer 42 between the two workpieces 37 . 38 be used for welding by roll cladding. The liner 42 consists of a material that has a higher oxygen affinity than the metal of the first material W1 and the second material W2. In the embodiment, therefore, the intermediate layer must have a greater oxygen affinity than aluminum. For example, a copper-based material may be used as the intermediate layer. Because of the greater oxygen affinity of the liner 42 creates a firm connection between the two workpiece parts 37 . 38 without the aluminum oxide layer or metal oxide layer 41 would have to be removed beforehand. It arises after joining and leaving a workpiece 25 according to 3 ,

In 6 is highly schematized the possibility of connecting the two workpiece parts 37 . 38 illustrated by capacitor discharge welding. It is the two workpiece parts 37 . 38 a high voltage was applied to which a capacitor was previously charged. In the embodiment is on one of the two workpiece parts 37 . 38 and according to the first workpiece part 37 a projection or a survey 46 available. The assessment 46 can be designed noppenähnlich with any cross-section, for example, a circular cross-section. The assessment 46 is at the first joining surface 39 available. Only about the survey 46 are the two workpiece parts 37 . 38 first together. Next to the survey 46 Thus, initially a gap remains between the two joining surfaces 39 . 40 the workpiece parts 37 . 38 , Will then the capacitor voltage to the two workpiece parts 37 . 38 created, flows through the survey 46 a current with high current density. The assessment 46 is melted by it and it can develop a plasma cloud. The molten material is starting from the survey 46 displaced by the gap to the outside. At the same time, the metal oxide layers become 41 at the joint surfaces 39 . 40 removed and the two workpiece parts 37 . 38 firmly welded together. The assessment 46 is preferably in a central portion of the respective joining surfaces 39 . 40 available. It creates a workpiece 25 as it is schematic in 2 is illustrated.

Another possibility to connect the two workpiece parts 37 . 38 is in 7 shown. In this process, the workpiece parts 37 . 38 connected by pulsed magnetic welding. At one of the joining surfaces 39 . 40 and according to the first joining surface 39 For example, there is a profile that is from the edge of the first joining surface 39 to a projecting point of the first joint surface 39 goes up. The first joining surface 39 may therefore have the shape of the shell of a pyramid, a truncated pyramid, a cone or a truncated cone. In the embodiment, the first joining surface 39 a conical surface shape, so that the first workpiece part 37 at the top 47 of the cone on the second workpiece part 38 is applied. The height of the gap between the two joining surfaces 39 . 40 thus assumes, starting from the tip 47 to the edge of the two joining surfaces 39 . 40 towards.

Via a coil, a magnetic field M is generated, at least on the first workpiece part 37 acts and causes a force there, the first workpiece part 37 on the second workpiece part 38 pushes down. By abruptly generating the Magnetic field M with a large field strength can be applied to the workpiece part 37 acting force cause a large forming speed, wherein the first joining surface 39 starting from the top 47 gradually to the second joint surface 40 of the second workpiece part 38 invests. In this application, which can be done at supersonic speed, the metal oxide layers 41 at the two joining surfaces 39 . 40 blown off and removed to the outside by the wedge-shaped gap. Also in this method, a firm connection between the two materials W1, W2 of the two workpiece parts 37 . 38 achieved and it creates a workpiece 25 as it is schematic in 2 is shown.

8th shows another way to connect the two workpiece parts 37 . 38 by friction welding. The two joining surfaces 39 . 40 run parallel to each other in this method and are aligned at right angles to a rotation axis D. In friction welding, for example, one of the two workpiece parts 37 . 38 driven to rotate about the axis of rotation D and simultaneously the two joining surface 39 . 40 the two workpiece parts 37 . 38 pressed against each other. In this case, the two metal oxide layers 41 at the joint surfaces 39 . 40 abraded, so to speak, and the metal oxide is pressed radially outward with respect to the axis of rotation D. Due to the frictional heat of the first material W1 and / or the second material W2 are liquefied and interconnected. Because of the different melting points of the metal oxide in the metal oxide layer 41 and the metal in the materials W1 and W2 is first the metal oxide layer 41 removed before welding together of the two materials W1, W2 takes place. Also in this method is a workpiece 25 made, as shown schematically in 2 is shown.

In the 10a to 10h are various stages of the forming process starting from the workpiece 25 until the finished cartridge case 20 illustrated. As a workpiece 25 can both in 2 schematically illustrated workpiece 25 be used, in which the two materials W1, W2 of the two workpiece parts 37 . 38 at the joint directly abut each other, or it may be the workpiece 25 according to 3 be used, in which at the joint between the first material W1 and the second material W2 an intermediate layer 42 is available.

Starting from the workpiece 25 from the two workpiece parts 37 . 38 is, for example, in a first step ( 10b ) a cup 55 (so-called "cup") produced. This can be done for example by ironing or drawing or extrusion.

Subsequently, in a second step, out of the cup 55 a cylindrical sleeve 56 produced, for example by extrusion ( 10d ). This forming process of the cup 55 in the cylindrical sleeve 56 can also have one or more intermediates 57 include, which exemplifies in 10c is illustrated.

The cylindrical sleeve 56 indicates the bottom section 21 on, which consists of the second material W2, to which the shell section 22 made of the first material W1. After making the cylindrical sleeve 56 in a third step ( 10e ) a detonation hole 58 in the bottom section 21 along the central longitudinal axis of the cylindrical sleeve 56 brought in. Besides, that will be the open end 24 having end portion 59 the cylindrical sleeve 56 formed by retraction, so that the diameter of the cylindrical sleeve 56 in the area of the end section 59 smaller than in the part of the almond section 22 that is attached to the bottom section 21 followed. In the embodiment, the end portion 59 a conical part 59a and one the open end of the cylindrical sleeve 56 having cylindrical part 59b on.

The retraction of the cylindrical sleeve 56 in the end section 59 is schematic in 10f shown. When retracting the end section 59 Due to the copper-free aluminum alloy of the first material W1 no heat input is necessary. The first material W1 can be reshaped without supplying heat first.

As in 10g illustrates, depending on the type of cartridge case 20 an ejector groove 60 in the bottom section 21 be introduced. The ejector groove 60 is annular and open radially outward. It is used in automatic weapons for ejecting the cartridge case 20 after ignition of the propellant charge.

The in the 10e to 10g Sub-steps shown can be performed in any order.

Finally, in the last step ( 10h ) an annular part in the region of the open end 24 separated, leaving the cartridge case 20 the desired length and a straight edge at the open end 24 receives. The separation can be carried out for example by means of a pulse magnetic separation process.

The invention relates to a method for producing a cartridge case 20 , The cartridge case 20 To reduce its weight, it consists of a light first material W1 in a shell section 22 and a solid second material W2 in a bottom portion 21 , As the first material W1 example, a copper-free aluminum alloy is used. The first material W1 is non-deformable without heat. As the second material W2 also an aluminum alloy can be used, which has a greater hardness compared to the aluminum alloy of the first material W1.

The two materials W1, W2 are used to produce a workpiece 25 connected with each other. For example, a casting method can be used for this purpose. Alternatively, it is also possible, a first workpiece part 37 from the first material W1 and a second workpiece part 38 from the second material W2 in the region of their respective joining surface 39 . 40 to connect with each other. In order to achieve a firm connection, one becomes at the joining surfaces 39 . 40 forming metal oxide layer 41 removed before or during the connection or by the use of an additional intermediate layer 42 rendered harmless.

LIST OF REFERENCE NUMBERS

20

cartridge case

21

bottom section

22

shell section

23

cavity

24

open end

25

workpiece

30

mold

31

partition wall

32

mold section

33

mold section

37

first workpiece part

38

second workpiece part

39

first joining surface

40

second joint surface

41

metal

42

liner

46

survey

47

top

55

cups

56

cylindrical sleeve

57

intermediate stage

58

touchhole

59

end

59a

conical part

59b

cylindrical part

60

Auswerferrille

D

axis of rotation

F

thrust

M

magnetic field

W1

first material

W2

second material

Claims (10)

Method for producing a cartridge case ( 20 ) comprising the following steps: - providing a first workpiece part ( 37 ) of a metal-containing first material (W1) with a first joining surface ( 39 ), wherein the first material (W1) is formed by an aluminum alloy that is free of a copper content, - providing a second workpiece part ( 38 ) of a metal-containing second material (W2) with a second joining surface ( 40 ), wherein the hardness of the second material (W2) is greater than that of the first material (W1), - surface bonding of the two workpiece parts ( 37 . 38 ) with their joining surfaces ( 39 . 40 ) to each other, wherein before or during the joining of the two workpiece parts ( 37 . 38 ) one each on the joint surfaces ( 39 . 40 ) existing metal oxide layer ( 41 ) or the metal oxide layers ( 41 ) with an intermediate layer ( 42 ), - reshaping of the two connected workpiece parts ( 37 . 38 ) produced workpiece ( 25 ) to a cartridge case ( 20 ), during the forming of the workpiece ( 25 ) first a cylindrical sleeve ( 56 ) with a jacket section ( 22 ) of the first material (W1) and a bottom portion ( 21 ) is produced from the second material (W2) whose open end portion ( 59 ) is subsequently reduced in diameter, and wherein the forming of the open end portion ( 59 ) to reduce its diameter without prior heat. Method according to claim 1, characterized in that the metal oxide layer ( 41 ) is removed before joining and the two workpiece parts ( 37 . 38 ) are then joined together by plating. Method according to claim 1 or 2, characterized in that the two workpiece parts ( 37 . 38 ) are joined together by plating and the intermediate layer ( 42 ) is made of a material having a higher oxygen affinity than the metal of the first and second materials (W1, W2). A method according to claim 1, characterized in that one of the joining surfaces ( 39 ) to its center of area ( 47 ) and the connection of the two workpiece parts ( 37 . 38 ) is done by pulse magnetic welding. A method according to claim 1, characterized in that the compound of both workpiece parts ( 37 . 38 ) by friction welding, wherein the metal oxide layers ( 41 ) by the relative rotation of the two joining surfaces ( 39 . 40 ) are removed from each other. A method according to claim 1, characterized in that one of the joining surfaces ( 39 . 40 ) a survey ( 46 ) and the connection of the two workpiece parts ( 37 . 38 ) is performed by capacitor discharge welding. Method for producing a cartridge case ( 20 ) comprising the following steps: - providing a mold ( 30 ) with two by a movable partition ( 31 ) separate mold sections ( 32 . 33 ), - filling a liquefied, metal-containing first material (W1) in the one mold section ( 32 ), wherein the first material (W1) is formed by an aluminum alloy, which is free of a copper content, - filling a liquefied, metal-containing second material (W2) in the respective other mold section ( 33 ), wherein the hardness of the second material (W2) is greater than that of the first material (W1), when the two materials (W1, W2) are completely solidified and cooled, - pulling out the partition ( 31 ) while the two materials (W1, W2) solidify and thereby connect flat with each other, so that a workpiece ( 25 ) of two interconnected workpiece parts ( 37 . 38 ), - removing the workpiece ( 25 ) from the mold ( 30 ), - reshaping of the two connected workpiece parts ( 37 . 38 ) produced workpiece ( 25 ) to a cartridge case ( 20 ), during the forming of the workpiece ( 25 ) first a cylindrical sleeve ( 56 ) with a jacket section ( 22 ) of the first material (W1) and a bottom portion ( 21 ) is produced from the second material (W2) whose open end portion ( 59 ) is subsequently reduced in diameter, and wherein the forming of the open end portion ( 59 ) to reduce its diameter without prior heat. Method according to one of the preceding claims, characterized in that the first material (W1) and / or the second material (W2) contains aluminum or nickel or brass. Method according to one of the preceding claims, characterized in that the second material (W2) comprises aluminum, brass or steel or consists of one of these materials. Method according to one of the preceding claims, characterized in that the thickness (D1) of the first part ( 37 ) is greater than the thickness (D2) of the second workpiece part ( 38 ).

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