WO1992000499A1

WO1992000499A1 - Mixed organic/metallic alloys for making projectiles

Info

Publication number: WO1992000499A1
Application number: PCT/FR1991/000527
Authority: WO
Inventors: Jean-Claude Sauvestre
Original assignee: Sauvestre Jean Claude
Priority date: 1990-07-02
Filing date: 1991-07-02
Publication date: 1992-01-09
Also published as: FR2664039A1; FR2664039B1; EP0537264A1

Abstract

Sub-calibre and standard calibre fin-stabilized projectiles for small, medium and large calibre kinetic energy ammunition, particularly hunting ammunition, are made of a mixed organic/metallic alloy consisting of at least one organic material for ensuring the integrity of the assembly and at least one metal filler. The projectiles can be used in ammunition of all calibres.

Description

Mixed organic-metallic alloys for making projectiles.

The present invention relates to sub-projectiles or projectiles with caliber stabilized by empennage for kinetic energy ammunition of small, medium and large caliber and in particular for hunting ammunition. Big game shooting is done using lead alloy bullet cartridges, whether or not coated with a metal casing. This bullet is commonly called a projectile when its diameter is equal to the caliber of the weapon and a sub-projectile when its diameter is less than the caliber of the weapon. In 12, 16 or 20 caliber hunting weapons, the stabilization of the projectile is obtained by a dragging or stabilizing element located at the rear of said projectile.

The most commonly used lead alloy, which also consists of antimony and tin, has the following advantages:

- High density (of the order of 11,300 kg / m ³ ) thus making it possible to have still sufficient kinetic energy at reasonable shooting distances.

- Relatively low cost of the basic material. - Easy implementation by conventional means of transformation.

In view of the above advantages, the disadvantages are significant:

- Increased medical surveillance of personnel working directly on said alloy

- Significant pollution of nature

- Significant concentration of this pollution in certain hunting areas and certain shooting ranges

- Possible metallization of the weapon tube by the lead alloy constituting the projectile

Sometimes ineffective stopping power of game mainly due to the too high ductility of the alloy used

- Resistance limited to mechanical stresses during the launching phase of the projectile (interior ballistics).

The object of the present invention is to replace lead alloys with an alloy composed in part of a organic material and metallic particles.

While retaining the advantages of the lead alloy, that is to say:

- High density even exceeding that of the lead alloy.

- Easy implementation with complete control of the geometry

- Cost price of the accessible part.

The major drawbacks cited for the lead alloy disappear:

- No special medical supervision of personnel working for the manufacture of products

- No pollution of nature

- Great power to stop game by mastering the composition of the hardness of the organic-metallic alloy and the geometry

- Total control of the mechanical resistance to mechanical stresses generated during the launching phase of the projectile. - No risk of metallization of the gun barrel.

The invention relates to a sub-projectile or projectile of caliber, stabilized by tail, for ammunition with kinetic energy of small, medium and large caliber and in particular for hunting ammunition characterized in that it is made of an organic mixed alloy- metallic consisting of at least one organic material ensuring the cohesion of the assembly and at least one metallic filler.

More particularly, the sub-projectile or projectile according to the invention is characterized: - in that the mixed organic-metallic alloy has physical and / or mechanical properties which are homogeneous longitudinally and radially

- in that the mixed organic-metallic alloy has physical and / or mechanical properties varying longitudinally and radially

- in that the organic material and / or the metallic charge of the mixed organic-metallic alloy make it possible to adapt the physical and / or mechanical properties according to a longitudinal variation - in that the organic material and / or the metallic charge of the mixed organic-metallic alloy makes it possible to adapt the physical and / or mechanical properties according to a radial variation - in that the organic material of the mixed organic alloy - metallic is loaded with carbon, glass or organic fibers

- in that the organic material contains an adjuvant such as a lubricant, a stabilizer or a colorant - in that there is a longitudinal variation in the density, from the highest value at the top to the lowest value on foot

- in that there is a longitudinal variation of the density, from the value of 14530 kg / m3 at the top to the value of 4730 kg / m3 at the bottom

- in that there is a longitudinal variation in resilience, the lowest value being at the top

- in that there is a longitudinal variation in resilience, varying from 4 J / m to 80 J / m

- in that there is a radial variation in the density, from the highest value at the core to the lowest value at the periphery

- in that there is a radial variation of the density, from the value of 14670 kg / m3 in the core to the value of

7680 kg / m ³ on the outskirts

- in that there is a radial variation in resilience, from the strongest value in the core to the lowest value in the periphery - in that there is a radial variation in resilience, in the value of 80 J / m at the core to the value of 10 J / m at the periphery

- in that it comprises a central element constituted by a mixed polyamide imide - tungsten alloy with a filling ratio of 0.74 and an external element constituted by a mixed polyamide 6,6 - tungsten alloy with a filling ratio of 0 , 36

- in that it consists of a mixed alloy such as a polyamide 6, 6 loaded with tungsten powder whose mass volume is between 8,500 and 13,500 kg / m ³

- in that it consists of a mixed alloy such as a polyamide 6.6 loaded with tungsten powder whose density is approximately 11,300 kg / m3 The invention will be better understood on reading the description below -After an exemplary embodiment, description made with reference to the accompanying drawings in which:

Figure 1 is a half-sectional view of a kinetic energy munition composed of a sub-projectile made of an alloy according to the present invention.

FIG. 2 is a view showing a magnification of the structure of the alloy along the section AA of FIG. 1.

Figure 3 is a half-sectional view of a sub-projectile having homogeneous physical and mechanical properties longitudinally and radially.

FIG. 4 is a half-section view of a simplified sub-projectile having longitudinally variable physical and mechanical properties.

FIG. 5 is a half-section view of a simplified sub-projectile having radially variable physical and mechanical characteristics.

FIG. 6 is a half-section view of a sub-projectile with high density and high brittleness at the head.

FIG. 1, specified above, represents an ammunition for a hunting weapon with a smooth or slightly striped core of caliber 12, 16 or 20 for example.

Figures 3, 4, 5 and 6 show the sub-projectile of this munition whose stability on the trajectory is ensured by a tail. Figure 1 is a half-sectional view which gives a use of the present invention for a hunting ammunition 1. The latter comprises a socket 2 of metallic material or not carrying a primer not shown, socket containing the propellant powder 3 and the projectile 4 constituted by a launching device 5 and a sub-projectile 6 composed of a body 7 and a tail unit. The launching device 5, composed of 2 elements with longitudinal separation, comprises teeth 9 which cooperate with grooves 10 formed on the body 7 of the sub-projectile 6. During the phase of the course of the projectile 4 in the core of the tube, the launching device 5 is therefore secured to the body 7 of the sub-projectile 6. From the exit of the tube _. the weapon, the longitudinal separation of the elements of the launching device 5 is achieved mainly thanks to the aerodynamic forces which are exerted on the front of said elements, thus releasing the sub-projectile 6 which achieves the intended objective.

Figure 2 gives the magnification of the structure of the mixed organic-metallic alloy used (in section AA of Figure 1)

The body 7 of the sub-projectile 6, made of this alloy, consists of metallic particles 11 embedded in an organic binder 12. This assembly obtained essentially by injection makes it possible to easily control the physical and mechanical properties for the intended application.

The potentially usable organic materials 12 are:

- thermoplastics which are injected into cold molds and which essentially comprise polyamides, polycarbonates, polyethylenes and polybutylenes.

- Thermosets which are injected into hot molds and which include in particular EPOXY resins, polyides and phenoplasts. All these materials can be loaded in variable proportions with carbon, glass or organic fibers (example: Kevlar). The ranges for the main physical and mechanical properties of the abovementioned organic materials are given below by family.

The metallic materials 11 introduced into the organic material 12 are either in the form of particles with dimensions of between 0.005 and several millimeters or in the form of fibers of diameter varying from 0.001 to 2 millimeters and of adjustable length.

Two main families make up these potentially usable metallic materials, excluding polluting materials such as depleted uranium and lead and precious metals such as silver, gold and platinum. The first family includes pure metals such as: tungsten, molybdenum, tantalum, iron, copper, aluminum, boron, nickel, cobalt and titanium.

The second family includes alloys, some of which are listed below:

- ferrous alloys: alloy steels example: 35 NCD 16 (Nickel + chromium + molybdenum)

- aluminum alloys: alloyed aluminum such as AU 4 G for example (aluminum + copper + magnesium) - copper alloys such as bronzes, brasses and cuproalus.

- titanium alloys such as TA6V (titanium + aluminum + vanadium)

The ranges of the main physical and mechanical properties of the aforementioned metallic materials are given below by family.

From these two tables it appears that a significant number of organic material-metallic material combinations is possible, possibly with an oriented choice of certain physical and / or mechanical characteristics to be obtained on the final alloy, depending on the cost price, its implementation and the intended use of the product produced. The minimum mechanical characteristics of said product correspond at least to those of the organic material used. The minimum density of the organic mixed alloy is slightly higher than that of the organic material with the lowest density, i.e. 880 kg / m ³ - The maximum density of the organic-metallic mixed alloy is obtained by considering stacking the most compact possible of the particles of the metallic charge 11 with a complete filling of the interstices with the organic material 12. In the case of stacking with perfectly arranged cubic grains, the density of the mixed alloy obtained can reach that of the highest density metallic load of 19,300 kg / m ³ . At the industrial level, compatible with mass production, this high limit has never been reached, but the production of an organic mixed alloy of 18,800 kg / m3 is perfectly possible (the filling rate of the metallic charge of

0.97 being the value used in certain metal alloys produced by other technologies such as the production of sintered alloys).

By way of example for a mixed alloy composed of an organic material 12 of polyamide 6, 6 type with a density

1140 kg / m3, and a metal charge 11 of tungsten powder type with a real density of 19,300 kg / m3, and considering that the structure of the tungsten powder is spherical in grain, grains arranged in a compact stack

(cubic structure with centered faces) allowing a maximum filling rate of 0.74, the density of the mixed alloy obtained is 14580 kg / m ³ . From the polyamide 6, 6 and tungsten powder composition, a mixed alloy of homogeneous longitudinal and radially homogeneous physical and mechanical characteristics and density 11,300 kg / m3 was produced, corresponding to that of a lead alloy for bullet of hunting. For lm ³ of this alloy, the proportions observed were 10,798 kg of tungsten powder (corresponding to a filling ratio of 0.56) and 502 kg of polyamide 6.6.

Figure 3 is a half-sectional view of the sub-projectile thus produced. The body 7 of the sub-projectile 6 has circular grooves 10 on the outer part, the function of which has been described previously. Other circular grooves 13 and adents 14 are formed at the foot of the body 7 of the sub-projectile 6 thus allowing the correct attachment of the tail 8 obtained by over-injection of a plastic alloy.

FIGS. 3a and 3b show that the body 7 of the sub-projectile 6 has homogeneous physical and mechanical characteristics both longitudinally and radially. To compare with shooting the polyamide 6,6 mixed alloy of tungsten powder with the lead alloy, it was produced in each of these materials, an equal number of sub-projectiles 6 with identical mass and geometry.

The results obtained are as follows: the mechanical strength of the mixed alloy during the pressure build-up phase was excellent as well as the ballistic dispersion obtained 100 meters from the weapon. In addition, a lower dispersion of the speed was observed at 100 meters than with the same sub-projectile provided with a body 7 of lead alloy. This is explained by the fact that this mixed alloy is very homogeneous during its implementation and does not create internal volume defects as with the lead alloy.

In the first three figures, the mixed organic-metallic alloy used for producing the body 7 of the sub-projectile 6 has homogeneous characteristics longitudinally and radially.

These homogeneous characteristics can be obtained by starting either from an intimate mixture of an organic material and a metallic charge (case developed above cf fig 3), or from an intimate mixture of several organic materials and a metallic charge, either of an intimate mixture of an organic material with several metallic charges and finally either of an intimate mixture of several organic materials with several metallic charges. In all cases, the mixture of organic material and metallic filler is carried out during the processing of the alloy. Furthermore, the organic material (s) can be reinforced with carbon, glass or organic fibers (example: KEVLAR). Adjuvants such as lubricants can also be introduced to facilitate processing (for example metal stearates), stabilizers for molecular chains (for example phenols and polyphenols) and colorants for essentially aesthetic purposes (for example oxides minerals such as calcium oxides).

FIG. 4 is a half-section view of a sub-projectile 6 consisting of a body 7 composed of three elements 15, 16 and 17 making it possible to obtain a longitudinal gradient of the physical and / or mechanical properties and of a empennage 8. In this figure, the connections of elements 15, 16 and 17 between them as well as the interfaces of the sub-projectile 6 with the launching device 5 and the empennage 8 itself have not been shown. diagrammed in dotted lines. Each element 15, 16 and 17 is composed of a mixed organic-metallic alloy with homogeneous characteristics longitudinally and radially. The implementation is carried out successively in a longitudinal fashion from head to foot or from foot to head. For example, element 15 is first produced which receives superinjection on the interface 18 element 16, which receives superinjection on the interface 19 element 17, which also receives superinjection on the interface 20 empennage 8 which itself is simply a plastic alloy.

For each element, this configuration makes it possible to make the best use of the physical and / or mechanical properties of the alloy as a function of the objectives to be ensured by each of them.

Figure 4a gives an illustration of the characteristics imposed on each element. Among other things, it was favored a low resilience (k) therefore a great ease of rupture upon impact of the element 15 placed at the head of the sub-projectile 6. This element easily fragments against the soft parts of a game.

Element 16, located in the middle of the sub-projectile 6 has the highest breaking strength (RT) to ensure the mechanical resistance of the sub-projectile to the mechanical stresses generated during the travel phase of the projectile 4 in the core of the barrel of the weapon. This element is not very fragile on impact (k) which makes it difficult to fragment when crossing the soft parts of the game but sufficiently resistant to properly attack the hard parts of said game.

The element 17, located at the foot of the sub-projectile 6 has a relatively high resistance to rupture (RT) and an elongation (Al). These characteristics allow it to have an intermediate behavior between the element 15 and the element 16 and to withstand all the transverse stresses generated by the transverse gradients induced by the pressure of the gases during the combustion of the propellant powder 3 and transmitted by the 'empennage 8. Furthermore, the density (MV) of the element 17 is the lowest to give good stability of the sub-projectile 6 on trajectory. The production of the following organic-metallic mixed alloy:

- polypropylene-tungsten for element 15, (density 14530 kg / m3, resilience 4 J / m, breaking strength 35 MPa) - polyamide imide - tungsten for element 16 (density 11300 kg / m3, resilience 80 J / m, breaking strength 110 MPa)

- polyamide6,6-steel for element 17 (density

4730 kg / m ³ , resilience 10 J / m, tensile strength 53 MPa) meets the imposed criteria.

The body 7 of the sub-projectile 6 may consist of only two elements, in particular retaining the head element identical to the element 15. FIG. 5 is a half-section view of a sub-projectile comprising a body 7 composed of three elements of tubular form for elements 21 and 22 and cylindrical for element 23 nested one inside the other, making it possible to obtain a radial gradient of the physical properties and / or mechanical and a tail 8 shown only in dotted lines. In this figure, the connections of the elements 21, 22, 23 are not shown, as well as the sub-projectile 6 - launching device 5 and sub-projectile 6 - tailplane 8 interfaces.

Each element 21, 22 or 23 is composed of a mixed organic-metallic alloy with homogeneous characteristics longitudinally and radially. The implementation is carried out successively from the axis of the sub-projectile 6 towards the outside. Element 23 is first produced which receives over-injection of element 22 which receives over-injection of element 21. The tail 8 is linked to element 23 during injection.

This configuration, different from the previous one, also makes it possible to exploit the physical and / or mechanical properties of the mixed alloy of each element as a function of the objectives targeted for each of them.

Figure 5a gives an illustration of the characteristics imposed on each element. For example, for element 21, an alloy was chosen which presents a compromise between its brittleness (low k), to fragment or peel easily in the soft parts of a game, and its resistance (RT and A% quite high ) to the mechanical stresses generated during the phase of travel of the projectile 4 in the core of the barrel of the weapon. For this element, it is not necessary to observe a high density (MV). The element 22 has an intermediate role making it possible to ensure good mechanical resistance of the elements between them during the course of the projectile 4 in the core of the barrel of the weapon and to supplement the destructive effects of the element 21 and those of the element 23. Its mechanical characteristics are on average intermediate between those of elements 21 and 23. Element 23 is the hard element of the sub-projectile 6. It has both a high resilience (k) to resist breaking by shock, a high resistance (RT) to allow to attack under good conditions the hard parts of a game and a high density to obtain surface kinetic energy (kinetic energy delivered by this element compared to the transverse surface of said element ) as high as possible. This kinetic energy is essential to ensure good penetration of hard parts of game.

The mixed organic-mechanical alloys polyamide 6, 6-steel for element 21, polysulfone-tungsten for element 22 and polyamide imide-tungsten for element 23 are an example of association to meet the requirements. The body 7 of the sub-projectile 6 may consist of only two elements, the external element having characteristics situated between those of elements 21 and 22 and the central element having characteristics identical to those of element 23.

The particular embodiment of the body 7 of the sub-projectile 6 made up of two elements, one central, the other peripheral, has led to the use of the following mixed alloys:

- for the central element: polyamide imide-tungsten with a filling rate of 0.74 (density of 14670 kg / m3, resilience 80 J / m, breaking strength 110 MPa)

- for the external element: polyamide 6,6-tungsten with a filling rate of 0.36 (density of 7680 kg / m3, resilience 10 J / m, breaking strength 53 MPa).

Figure 6 is a half-sectional view schematically showing a sub-projectile 6 comprising a body 7 by combination of elements of type 15, 16, 17 specified in Figure 4 and of elements. type 21, 22, 23 indicated by FIG. 5. This combination makes it possible to obtain both a longitudinal gradient and a radial gradient of the physical and / or mechanical properties.

As the sub-projectile 6 is stabilized on the trajectory by the tail 8, it is mandatory to have the center of gravity

(G) as far forward as possible to obtain the static margin marked 1 as large as possible (1 being the distance between the center of gravity (G) and the center of thrust (P) or aerodynamic focus). This is achieved through the use of mixed organic-metallic alloys using very dense metallic charges at the head of the sub-projectile 6 and less dense metallic charges at the foot of this same sub-projectile. These metallic charges are associated with organic materials so as to ensure increased embrittlement at the head of the sub-projectile and decreased at the foot of this same sub-projectile. FIG. 6a illustrates this type of embodiment.

Other variants of mixed organic-metallic alloys are possible without departing from the scope of the invention. It is possible for example to preorient the elements of the metallic charge and to inject the organic material to bind them together. It is also possible to obtain a quasi-continuous curve of longitudinal and / or radial gradient by multiplying the number of elements placed longitudinally (cf. FIG. 4) and / or the number of elements placed radially (cf. FIG. 5 ).

The invention described here applied to hunting ammunition can be adapted to any other type of small, medium and large caliber ammunition and very particularly to shooting practice ammunition.

Claims

RESELL TO TONS

1 - Sub-projectile or caliber projectile, stabilized by tail, for kinetic energy ammunition of small, medium and large caliber and in particular for hunting ammunition characterized in that it is made of an organic-metallic mixed alloy made up of less of an organic material ensuring the cohesion of the whole and at least of a metallic charge.

2 - Sub-ectile or projectile, according to claim 1, characterized in that the mixed organic-metallic alloy has physical and / or mechanical properties homogeneous longitudinally and radially

3 - Sub-projectile or projectile, according to claim 1, characterized in that the mixed organic-metallic alloy has physical and / or mechanical properties varying longitudinally and radially

4 - Sub-projectile or projectile, according to claim or 3, characterized in that the organic material and / or the metallic charge of the mixed organic-metallic alloy allow the physical and / or mechanical properties to be adapted according to a longitudinal variation

5 - Sub-projectile or projectile, according to claim or 3, characterized in that the organic material and / or the metallic charge of the mixed organic-metallic alloy allow the physical and / or mechanical properties to be adapted according to a radial variation

6 - Sub-projectile or projectile, according to one of claims 1 to 5, characterized in that the organic material of the mixed organic-metallic alloy is loaded with carbon, glass or organic fibers 7 - Sub-projectile or projectile according to one of claims 1 to 6, characterized in that the organic material contains an adjuvant such as a lubricant, a stabilizer or a dye

8 - Sub-projectile or projectile, according to one of claims 1, 3, 4, 5, 6 or 7 characterized in that there is a longitudinal variation of the density, of the highest value at the top to the lowest value at the bottom

9 - Sub-projectile or projectile, according to claim 8, characterized in that there is a longitudinal variation of the density, from the value of 14530 kg / m ³ at the head to the value of 4730 kg / m ³ at the foot

10 - Sub-projectile or projectile, according to one of claims 1, 3, 4, 5, 6, 7, 8 or 9, characterized in that there is a longitudinal variation of the resilience, the lowest value being on your mind

11 - Sub-projectile or projectile, according to claim 10, characterized in that there is a longitudinal variation of the resilience, varying from 4 J / m to 80 J / m

12 - Sub-projectile or projectile, according to one of claims 1, 3, 4, 5, 6, 7, 8, 9, 10 or 11, characterized in that there is a radial variation of the density, from the highest value at the core to the lowest value at the periphery

13 - Sub-projectile or projectile, according to claim 12, characterized in that there is a radial variation of the density, from the value of 14670 kg / m ³ in the core to the value of 7680 kg / m ³ in the periphery

14 - Sub-projectile or projectile, according to one. One of claims 1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or 13, characterized in that there is a radial variation of resilience, from the highest value in the core to the lowest value in the periphery

15 - Sub-projectile or projectile, according to claim 14, characterized in that there is a radial variation of the resilience, from the value of 80 J / m in the core to the value of 10 J / m in the periphery

16 - Sub-projectile or projectile, according to one of claims 1, 5, 6, 7, 12, 13, 14 or 15, characterized in that it comprises a central element constituted by a mixed polyamide imide - tungsten alloy with a filling rate of 0.74 and an external element constituted by a mixed polyamide 6.6 - tungsten alloy with a filling rate of 0.36

17 - Sub-projectile or projectile, according to one of Claims 1 or 2, characterized in that it consists of a mixed alloy such as a polyamide 6,6 charged with tungsten powder whose density is between 8,500 and 13,500 kg / m ³

18 - Sub-projectile or projectile, according to claim 17, characterized in that it is constituted by a mixed alloy such as a polyamide 6,6 charged with tungsten powder whose density is approximately 11,300 kg / m ³