EP3349929B1 - Penetrator comprising a core surrounded by a ductile sheath and process for manufacturing such a penetrator - Google Patents

Penetrator comprising a core surrounded by a ductile sheath and process for manufacturing such a penetrator Download PDF

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Publication number
EP3349929B1
EP3349929B1 EP16757687.5A EP16757687A EP3349929B1 EP 3349929 B1 EP3349929 B1 EP 3349929B1 EP 16757687 A EP16757687 A EP 16757687A EP 3349929 B1 EP3349929 B1 EP 3349929B1
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EP
European Patent Office
Prior art keywords
tungsten
core
sheath
mass
cobalt
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EP16757687.5A
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German (de)
French (fr)
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EP3349929C0 (en
EP3349929A1 (en
Inventor
Rafael CURY
Laurent DARTUS
Fabien ISSARTEL
Hervé COUQUE
Nicolas Eches
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Knds Ammo France
Cime Bocuze SA
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Cime Bocuze SA
Nexter Munitions SA
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Publication of EP3349929A1 publication Critical patent/EP3349929A1/en
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Publication of EP3349929B1 publication Critical patent/EP3349929B1/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B12/00—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material
    • F42B12/02—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect
    • F42B12/04—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect of armour-piercing type
    • F42B12/06—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect of armour-piercing type with hard or heavy core; Kinetic energy penetrators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/06—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
    • B22F7/062—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/045—Alloys based on refractory metals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B12/00—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material
    • F42B12/72—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the material
    • F42B12/74—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the material of the core or solid body
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B14/00—Projectiles or missiles characterised by arrangements for guiding or sealing them inside barrels, or for lubricating or cleaning barrels
    • F42B14/06—Sub-calibre projectiles having sabots; Sabots therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B14/00—Projectiles or missiles characterised by arrangements for guiding or sealing them inside barrels, or for lubricating or cleaning barrels
    • F42B14/06—Sub-calibre projectiles having sabots; Sabots therefor
    • F42B14/061—Sabots for long rod fin stabilised kinetic energy projectiles, i.e. multisegment sabots attached midway on the projectile

Definitions

  • the technical field of the invention is that of heavy metal penetrators and in particular that of penetrators used to produce large caliber sub-caliber projectiles (calibrated greater than or equal to 25 mm).
  • projectiles are most often referred to as arrow projectiles. They feature a sub-caliber penetrator or bar that is fired by a weapon using a weapon-caliber sabot.
  • the penetrator For a projectile of caliber 120 mm, the penetrator generally has a diameter of 20 to 30 mm and the sabot allowing the shot is formed of a set of sectors made of light material (aluminum alloy for example).
  • Licences US8580188B2 , FR-2521717 And FR-2661739 describe examples of arrow projectiles.
  • penetrators are most often made of an alloy with a high tungsten content.
  • Such alloys are sensitive to the transverse stresses they receive during impact on an inclined target or else during interaction with reactive protection.
  • the transverse shocks cause the penetrator to break, which reduces the perforating power of the penetrator after passing such targets.
  • a penetrator comprising a core formed from an alloy comprising 90 to 97% by mass of tungsten and which is surrounded by a peripheral sheath of a tungsten alloy that is more ductile than the material of the core.
  • the sheath of this penetrator has a tungsten content between 85% and 91%.
  • the tungsten percentage of the sheath is relatively close to that of the core and this penetrator therefore has insufficient bending resistance performance.
  • Such a penetrator is not suited to current needs for making arrow projectiles having an elongation, that is to say a ratio (L/D) of the length (L) of the penetrator to the diameter (D) of the penetrator, which is important.
  • the patent EP-1940574 proposes to sinter the core and the sheath in the same mould.
  • the separation between sheath and core is ensured by a particular funnel associated with a tube which separates the core zone and the sheath zone.
  • the tube and funnel are removed.
  • the cladding and core materials are then in contact and sintering can be performed.
  • Such a method has the disadvantage of leaving between cladding and core a transition zone having a thickness between 25 micrometers and 200 micrometers.
  • This zone is formed of a material whose composition and characteristics are intermediate between those of the core and of the cladding.
  • Such a transition zone associates, like the core and the cladding, tungsten nodules and a gamma phase. The size of the tungsten nodules and the composition of the gamma phase of this zone are obligatorily different from those of the core and the sheath. If it were otherwise, there would be no such transition zone.
  • this transition zone thickness, positioning relative to the axis of the indenter, etc.
  • the ductility of the cladding obtained with this process is therefore slightly higher than that of the core, of the order of 5 to 10%.
  • the object of the invention is to propose an indenter structure in which the adhesion between sheath and core is excellent, even with a difference in tungsten content between sheath and core.
  • the penetrator according to the invention can then have a sheath ductility which is greater than that of the known tungsten sheath penetrators.
  • the subject of the invention is a heavy metal penetrator with a high tungsten content comprising a central part or core formed of an alloy comprising from 85 to 97% by mass of tungsten associated with additional metals and which is surrounded by a peripheral sheath of a tungsten alloy that is more ductile than the material of the core, penetrator characterized in that the sheath is made of an alloy comprising from 30% to 72% by mass of tungsten, the core comprising tungsten nodules bonded by a matrix of a gamma ⁇ C phase associating tungsten with the additional metals, the two gamma phases being connected to each other continuously without a transition zone.
  • the gamma phases of the ⁇ C core and of the ⁇ G cladding will have a composition combining tungsten, nickel, cobalt and possibly iron.
  • the core may comprise 85% by mass of tungsten and the cladding 38% by mass of tungsten, the gamma phases of the ⁇ C core and of the ⁇ G cladding having compositions combining Tungsten, Nickel, and Cobalt.
  • the core may comprise 89% by mass of tungsten and the cladding 68% by mass of tungsten, the gamma phases of the ⁇ C core and of the ⁇ G cladding having compositions combining Tungsten, Nickel and Cobalt.
  • the alloy of the core may comprise 95% by mass of Tungsten, 2% by mass of Nickel, 1.5% by mass of Cobalt and 2% by mass of Fe and the sheath 70% in mass of tungsten, the gamma phases of the ⁇ C core and of the ⁇ G sheath having compositions combining Tungsten, Nickel, Cobalt and Iron.
  • the invention also relates to a method for producing such an indenter.
  • FIG. 1 shows an arrow projectile 1 which comprises in a conventional way a sabot 2 made of light material (such as an aluminum alloy), sabot formed of several segments and which surrounds a sub-caliber penetrator 3.
  • a sabot 2 made of light material (such as an aluminum alloy), sabot formed of several segments and which surrounds a sub-caliber penetrator 3.
  • the penetrator comprises a conical front part 3a and carries at its rear part 3b a stabilizer 4 ensuring its stabilization on trajectory.
  • the very structure of the indenter 3 will be described later.
  • the sabot carries a belt 5, made of plastic material, and which seals against propellant gases during firing in the barrel of a weapon (not shown).
  • the gases of the propellant charge exert their thrust at the level of a rear part 6 of the sabot which is in the caliber and which constitutes what is called the thrust plate.
  • Sabot 2 is intended to allow the projectile to be fired in the weapon. It is made up of several segments (most often three) which surround the indenter3 and which are in contact two by two at the joint planes.
  • the segments of the sabot 2 deviate from the penetrator 3 under the action of the aerodynamic pressure which is exerted at the level of the front part (AV) of the sabot 2.
  • Shape-matching means (not shown), for example a thread, are interposed between the sabot 2 and the indenter 3 to drive the latter.
  • FIG. 2 shows more precisely the structure of the penetrator 3 which comprises a central part or core 7 which is surrounded by a peripheral sheath 8.
  • the core is formed from an alloy comprising from 85% to 97% by weight of tungsten and the sheath is made from an alloy comprising from 30% to 72% by weight of tungsten.
  • Tungsten is alloyed, both at the level of the core and of the sheath, with addition metals such as Nickel which will always be associated with Cobalt with or without iron.
  • the material comprises nodules 9 of phase ⁇ tungsten with a centered cubic crystalline structure which are bonded together by a matrix 10 of a gamma ⁇ C phase combining tungsten with nickel, with cobalt with or without iron (Fe), with a face-centered cubic crystal structure.
  • the tungsten content of the core is between 85% and 97%, which results in a core density of the order of 17 g/cm 3 .
  • the core 7 is formulated so as to have an elastic limit greater than or equal to 1100 MPa (Mega Pascals).
  • the ductility is around 6% and its Charpy resilience (unnotched test according to ISO 179-1 standard) is 80 J/cm 2 .
  • the material essentially comprises a matrix 11 of a gamma ⁇ G phase essentially associating tungsten with Nickel and Cobalt with or without Fe, and with a face-centered cubic crystalline structure which is the sign that this sheath has a high resilience.
  • the percentage of tungsten of the sheath 8 is between 30% and 72%, which leads to a density of this sheath which can vary between 10 g/cm3 and 15 g/cm3.
  • the alloy of the sheath 8 will be formulated so as to have a ductility greater than 7% and a high resilience: Charpy resilience (non-notched test according to standard ISO 179-1) greater than or equal to 200 J/cm 2 .
  • the sheath 8 is therefore more ductile than the core 7.
  • the gamma ⁇ C phase of the core combines tungsten with nickel and cobalt (with or without iron)
  • the gamma ⁇ G phase of the cladding will also include nickel and cobalt (with or without iron) as additional metals.
  • THE figures 5a and 5b show that after shaping the indenter 3, the matrices 10 and 11 of the core 8 and of the sheath 7 (matrices formed by the gamma phases of the core and of the sheath) are connected to each other in a continuous manner without transition zone.
  • the zones marked with the arrows Z1 and Z2 the figure 5b is at twice the magnification of the figure 5a ).
  • step A to manufacture an alloy comprising 85% to 97% by mass of tungsten, the powders of Tungsten, Nickel, Cobalt and possibly Iron are mixed homogeneously and pre-compressed in the form of a bar. which will constitute the heart.
  • a sheath 8 of an alloy comprising 30% to 72% by mass of tungsten associated with additional metals comprising nickel, cobalt and optionally iron is produced.
  • the materials are mixed homogeneously and then compressed in a tool which comprises a cylindrical core having a diameter equal to or greater than the internal diameter desired for the sheath.
  • the rest of the compression tooling is conventional.
  • the cladding and the core are assembled by sintering.
  • the alloys are consolidated at temperatures between 1400°C and 1600°C.
  • the sintering makes it possible to ensure the continuity of the gamma phases between the cladding and the core.
  • the thickness of the sheath 8 may thus vary between 5 mm and 9 mm for an indenter with an external diameter of 35 mm.
  • Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.
  • the core is formed of 85% by mass of tungsten, and having a density of 16.5 g/cm 3 , an elastic limit of 1800 MPa, a ductility of 10% and an unnotched Charpy resilience of 150 J/cm 2 .
  • the core alloy comprises 85% by mass of Tungsten, 15% by mass of Nickel and 5% by mass of Cobalt.
  • the sheath has a density of 11.2 g/cm 2 , an elastic limit of 1400 MPa, a ductility of 18% and an unnotched Charpy resilience of 400 J/cm 2 .
  • the sheath alloy comprises (proportions by mass): 38.0% Tungsten, 40% Nickel and 22% Cobalt.
  • This penetrator (and its blank) was manufactured by implementing the process described above.
  • Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.
  • the core is formed of 89% by mass of tungsten, and having a density of 17.1 g/cm 3 , an elastic limit of 1500 MPa, a ductility of 9% and an unnotched Charpy resilience of 300 J/cm 2 .
  • the core alloy comprises 89% by mass of Tungsten, 7.5% by mass of Nickel and 3.5% by mass of Cobalt.
  • the sheath is formed of 68% by mass of tungsten and having a density of 14.1 g/cm 2 , an elastic limit of 2000 MPa, a ductility of 11% and an unnotched Charpy resilience of 400 J/cm 2 .
  • the sheath alloy comprises (proportions by mass): 68% Tungsten, 22% Nickel and 10% Cobalt.
  • This penetrator (and its blank) was manufactured by implementing the process described above.
  • Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.
  • the core is formed of 95% by mass of tungsten, and having a density of 18.3 g/cm 3 , an elastic limit of 1300 MPa, a ductility of 7% and an unnotched Charpy resilience of 50 J/cm 2 .
  • the core alloy comprises 95% by mass of Tungsten, 2% by mass of nickel, 1.5% by mass of cobalt and 2% by mass of iron.
  • the sheath is formed of 70.0% by mass of tungsten and having a density of 14.0 g/cm 2 , an elastic limit of 2000 MPa, a ductility of 9% and an unnotched Charpy resilience of 300 J/cm 2 .
  • the sheath alloy comprises (proportions by mass): 70.0% by mass of Tungsten, 18% by mass of Nickel, 10% by mass of Cobalt and 2% by mass of Fe.
  • This penetrator (and its blank) was manufactured by implementing the process described above.

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Description

Le domaine technique de l'invention est celui des pénétrateurs en métal lourd et en particulier celui des pénétrateurs utilisés pour réaliser des projectiles sous calibrés de gros calibre (calibré supérieur ou égal à 25 mm).The technical field of the invention is that of heavy metal penetrators and in particular that of penetrators used to produce large caliber sub-caliber projectiles (calibrated greater than or equal to 25 mm).

Ces projectiles sont le plus souvent appelés projectiles flèches. Ils comportent un pénétrateur ou barreau sous-calibré qui est tiré par une arme à l'aide d'un sabot au calibre de l'arme.These projectiles are most often referred to as arrow projectiles. They feature a sub-caliber penetrator or bar that is fired by a weapon using a weapon-caliber sabot.

Pour un projectile de calibre 120 mm, le pénétrateur a généralement un diamètre de 20 à 30 mm et le sabot permettant le tir est formé d'un ensemble de secteurs en matériau léger (alliage d'aluminium parexemple).For a projectile of caliber 120 mm, the penetrator generally has a diameter of 20 to 30 mm and the sabot allowing the shot is formed of a set of sectors made of light material (aluminum alloy for example).

Les brevets US8580188B2 , FR-2521717 et FR-2661739 décrivent des exemples de projectiles flèches.Licences US8580188B2 , FR-2521717 And FR-2661739 describe examples of arrow projectiles.

Pour augmenter l'efficacité pénétrante des projectiles flèches, les pénétrateurs sont le plus souvent réalisés en un alliage à haute teneur en tungstène.To increase the penetrating efficiency of arrow projectiles, penetrators are most often made of an alloy with a high tungsten content.

De tels alliages sont sensibles aux sollicitations transversales qu'ils reçoivent lors de l'impact sur une cible inclinée ou bien lors de l'interaction avec une protection réactive. Les chocs transversaux provoquent la rupture du pénétrateur ce qui réduit le pouvoir perforant du pénétrateur après passage de telles cibles.Such alloys are sensitive to the transverse stresses they receive during impact on an inclined target or else during interaction with reactive protection. The transverse shocks cause the penetrator to break, which reduces the perforating power of the penetrator after passing such targets.

Il est connu de doter les pénétrateurs d'une chemise périphérique en un matériau plus ductile assurant une résistance à la flexion pour le pénétrateur.It is known to provide penetrators with a peripheral jacket made of a more ductile material providing resistance to bending for the penetrator.

On connaît par exemple par le brevet EP-1940574 un pénétrateur comportant un coeur formé d'un alliage comprenant de 90 à 97% en masse de tungstène et qui est entouré d'une gaine périphérique d'un alliage de tungstène plus ductile que le matériau du coeur.We know, for example, from the patent EP-1940574 a penetrator comprising a core formed from an alloy comprising 90 to 97% by mass of tungsten and which is surrounded by a peripheral sheath of a tungsten alloy that is more ductile than the material of the core.

La gaine de ce pénétrateur a une proportion en tungstène comprise entre 85% et 91%.The sheath of this penetrator has a tungsten content between 85% and 91%.

Le pourcentage en tungstène de la gaine est relativement proche de celui du coeur et ce pénétrateur a donc des performances de résistance à la flexion insuffisantes.The tungsten percentage of the sheath is relatively close to that of the core and this penetrator therefore has insufficient bending resistance performance.

Un tel pénétrateur n'est pas adapté aux besoins actuels de réalisation de projectiles flèches ayant un allongement, c'est à dire un rapport (L/D) de la longueur (L) du pénétrateur sur le diamètre (D) du pénétrateur, qui est important.Such a penetrator is not suited to current needs for making arrow projectiles having an elongation, that is to say a ratio (L/D) of the length (L) of the penetrator to the diameter (D) of the penetrator, which is important.

On cherche en effet à réaliser aujourd'hui des pénétrateurs ayant un allongement dépassant 20 (L/D > 20). Ceci conduit à des pénétrateurs de plus de 500 mm de long pour un diamètre de 25 à 35 mm. De tels pénétrateurs sont particulièrement sensibles aux impacts sur des cibles inclinées.Today, in fact, attempts are made to produce penetrators with an elongation exceeding 20 (L/D > 20). This leads to penetrators over 500 mm long for a diameter of 25 to 35 mm. Such penetrators are particularly sensitive to impacts on inclined targets.

Il n'est cependant pas aisé de donner à la gaine une ductilité supérieure à celle du coeur. Par ailleurs, il est également nécessaire d'assurer une liaison entre le matériau du coeur et celui de la gaine. Si cette liaison est insuffisante, les efforts radiaux ou longitudinaux conduisent à une séparation de ces éléments lors de l'impact ou même comme suite au tir.However, it is not easy to give the sheath a ductility greater than that of the core. Furthermore, it is also necessary to ensure a connection between the material of the core and that of the cladding. If this connection is insufficient, the radial or longitudinal forces lead to a separation of these elements during the impact or even as a result of the shot.

Pour assurer la liaison, le brevet EP-1940574 propose de procéder à un frittage du coeur et de la gaine dans un même moule. La séparation entre gaine et coeur est assurée par un entonnoir particulier associé à un tube qui sépare la zone de coeur et la zone de gaine. Après mise en place des matériaux de la gaine et du coeur, le tube et l'entonnoir sont retirés. Les matériaux de gaine et de coeur sont alors en contact et le frittage peut être réalisé.To ensure the connection, the patent EP-1940574 proposes to sinter the core and the sheath in the same mould. The separation between sheath and core is ensured by a particular funnel associated with a tube which separates the core zone and the sheath zone. After placement of the sheath and core materials, the tube and funnel are removed. The cladding and core materials are then in contact and sintering can be performed.

Un tel procédé présente l'inconvénient de laisser subsister entre gaine et coeur une zone de transition ayant une épaisseur entre 25 micromètres et 200 micromètres. Cette zone est formée d'un matériau dont la composition et les caractéristiques sont intermédiaires entre celles du coeur et de la gaine. Une telle zone de transition associe, tout comme le coeur et la gaine, des nodules de tungstène et une phase gamma. La taille des nodules de tungstène et la composition de la phase gamma de cette zone sont obligatoirement différentes de celles du coeur et de la gaine. S'il en était autrement, il n'y aurait pas une telle zone de transition.Such a method has the disadvantage of leaving between cladding and core a transition zone having a thickness between 25 micrometers and 200 micrometers. This zone is formed of a material whose composition and characteristics are intermediate between those of the core and of the cladding. Such a transition zone associates, like the core and the cladding, tungsten nodules and a gamma phase. The size of the tungsten nodules and the composition of the gamma phase of this zone are obligatorily different from those of the core and the sheath. If it were otherwise, there would be no such transition zone.

L'inconvénient d'une telle zone de transition est qu'elle constitue une interface fragilisant le barreau ainsi réalisé.The disadvantage of such a transition zone is that it constitutes an interface weakening the bar thus produced.

Plus spécifiquement encore, la géométrie de cette zone de transition (épaisseur, positionnement par rapport à l'axe du pénétrateur...) n'est pas maîtrisée.More specifically still, the geometry of this transition zone (thickness, positioning relative to the axis of the indenter, etc.) is not controlled.

Il en résulte des variations du positionnement radial de cette zone de transition le long du pénétrateur, variations d'autant plus marquées pour un pénétrateur de grand allongement. Il en résulte également une résistance de cette interface qui est très variable le long du pénétrateur, ce qui diminue les performances de perforation.This results in variations in the radial positioning of this transition zone along the indenter, variations which are all the more marked for an indenter of great elongation. This also results in a resistance of this interface which is very variable along the indenter, which reduces the perforation performance.

Par ailleurs, le procédé décrit par le brevet EP-1940574 impose un taux de tungstène de la gaine qui est relativement proche du taux de tungstène du coeur.Moreover, the process described by the patent EP-1940574 imposes a cladding tungsten content which is relatively close to the core tungsten content.

La ductilité de la gaine obtenue avec ce procédé est donc peu supérieure à celle du coeur, de l'ordre de 5 à 10%.The ductility of the cladding obtained with this process is therefore slightly higher than that of the core, of the order of 5 to 10%.

L'invention a pour but de proposer une structure de pénétrateur dans laquelle l'adhérence entre gaine et coeur est excellente, même avec une différence de taux de tungstène entre gaine et coeur.The object of the invention is to propose an indenter structure in which the adhesion between sheath and core is excellent, even with a difference in tungsten content between sheath and core.

Le pénétrateur selon l'invention peut alors avoir une ductilité de gaine qui est supérieure à celle des pénétrateurs à gaine de tungstène connus.The penetrator according to the invention can then have a sheath ductility which is greater than that of the known tungsten sheath penetrators.

Ainsi, l'invention a pour objet un pénétrateur en métal lourd à haute teneur en tungstène comportant une partie centrale ou coeur formé d'un alliage comprenant de 85 à 97% en masse de tungstène associé à des métaux additionnels et qui est entouré d'une gaine périphérique d'un alliage de tungstène plus ductile que le matériau du coeur, pénétrateur caractérisé en ce que la gaine est réalisée en un alliage comprenant de 30% à 72% en masse de tungstène, le coeur comprenant des nodules de tungstène liés par une matrice d'une phase gamma γC associant le tungstène aux métaux additionnels, les deux phases gamma étant reliées l'une à l'autre de façon continue sans zone de transition.Thus, the subject of the invention is a heavy metal penetrator with a high tungsten content comprising a central part or core formed of an alloy comprising from 85 to 97% by mass of tungsten associated with additional metals and which is surrounded by a peripheral sheath of a tungsten alloy that is more ductile than the material of the core, penetrator characterized in that the sheath is made of an alloy comprising from 30% to 72% by mass of tungsten, the core comprising tungsten nodules bonded by a matrix of a gamma γ C phase associating tungsten with the additional metals, the two gamma phases being connected to each other continuously without a transition zone.

Avantageusement, les phases gamma du coeur γC et de la gaine γG auront une composition associant le tungstène, le nickel, le cobalt et éventuellement le fer.Advantageously, the gamma phases of the γ C core and of the γ G cladding will have a composition combining tungsten, nickel, cobalt and possibly iron.

Selon un mode de réalisation, le coeur pourra comprendre 85% en masse de tungstène et la gaine 38% en masse de tungstène, les phases gamma du coeur γC et de la gaine γG ayant des compositions associant Tungstène, Nickel,et Cobalt.According to one embodiment, the core may comprise 85% by mass of tungsten and the cladding 38% by mass of tungsten, the gamma phases of the γ C core and of the γ G cladding having compositions combining Tungsten, Nickel, and Cobalt.

Selon un autre mode de réalisation, le coeur pourra comprendre 89% en masse de tungstène et la gaine 68% en masse de tungstène, les phases gamma du coeur γC et de la gaine γG ayant des composition associant Tungstène, Nickel et Cobalt.According to another embodiment, the core may comprise 89% by mass of tungsten and the cladding 68% by mass of tungsten, the gamma phases of the γ C core and of the γ G cladding having compositions combining Tungsten, Nickel and Cobalt.

Selon encore un autre mode de réalisation, l'alliage du coeur pourra comprendre 95% en masse de Tungstène, 2% en masse de Nickel, 1,5% en masse de Cobalt et 2% en masse de Fe et la gaine 70% en masse de tungstène, les phases gamma du coeur γC et de la gaine γG ayant des compositions associant Tungstène, Nickel, Cobalt et Fer.According to yet another embodiment, the alloy of the core may comprise 95% by mass of Tungsten, 2% by mass of Nickel, 1.5% by mass of Cobalt and 2% by mass of Fe and the sheath 70% in mass of tungsten, the gamma phases of the γ C core and of the γ G sheath having compositions combining Tungsten, Nickel, Cobalt and Iron.

L'invention a également pour objet un procédé permettant de réaliser un tel pénétrateur.The invention also relates to a method for producing such an indenter.

Ce procédé de fabrication d'un pénétrateur en métal lourd à haute teneur en tungstène est caractérisé en ce qu'il comprend les étapes suivantes (qui conduisent à la réalisation d'un ébauché de ce pénétrateur) :

  • fabrication d'un coeur composé de poudres compactées comprenant de 85% à 97% en masse de tungstène associé à des métaux additionnels comprenant le nickel, le cobalt avec ou sans Fer,
  • fabrication d'une gaine composée de poudres compactées comprenant de 30% à 72% en masse de tungstène associé à des métaux additionnels comprenant le nickel, le cobalt avec ou sans Fer,
  • assemblage par frittage de la gaine et du coeur.
This process for manufacturing a heavy metal penetrator with a high tungsten content is characterized in that it comprises the following steps (which lead to the production of a blank of this penetrator):
  • manufacture of a core composed of compacted powders comprising from 85% to 97% by mass of tungsten associated with additional metals including nickel, cobalt with or without iron,
  • manufacture of a sheath composed of compacted powders comprising from 30% to 72% by mass of tungsten associated with additional metals including nickel, cobalt with or without iron,
  • assembly by sintering of the sheath and the core.

L'invention sera mieux comprise à la lecture de la description qui va suivre de modes particuliers de réalisation, description faite en référence aux dessins annexés et dans lesquels :

  • la figure 1 montre l'architecture générale d'un projectile sous calibré de type flèche,
  • la figure 2 montre en coupe longitudinale partielle un pénétrateur selon l'invention,
  • la figure 3 est une micrographie montrant la structure du coeur du pénétrateur selon l'invention,
  • la figure 4 est une micrographie montrant la structure de la gaine du pénétrateur selon l'invention,
  • la figure 5a est une micrographie montrant la liaison entre gaine et coeur, et
  • la figure 5b est un grossissement de la micrographie de la figure 5a.
The invention will be better understood on reading the following description of particular embodiments, description made with reference to the accompanying drawings and in which:
  • there figure 1 shows the general architecture of an arrow-type subcaliber projectile,
  • there figure 2 shows in partial longitudinal section an indenter according to the invention,
  • there picture 3 is a micrograph showing the structure of the core of the penetrator according to the invention,
  • there figure 4 is a micrograph showing the structure of the sheath of the indenter according to the invention,
  • there figure 5a is a micrograph showing the connection between sheath and core, and
  • there figure 5b is a magnification of the micrograph of the figure 5a .

La figure 1 montre un projectile flèche 1 qui comporte d'une façon classique un sabot 2 réalisé en matériau léger (tel qu'un alliage d'aluminium), sabot formé de plusieurs segments et qui entoure un pénétrateur 3 sous-calibré.There figure 1 shows an arrow projectile 1 which comprises in a conventional way a sabot 2 made of light material (such as an aluminum alloy), sabot formed of several segments and which surrounds a sub-caliber penetrator 3.

Le pénétrateur comporte une partie avant 3a conique et porte à sa partie arrière 3b un empennage 4 assurant sa stabilisation sur trajectoire. La structure même du pénétrateur 3 sera décrite par la suite.The penetrator comprises a conical front part 3a and carries at its rear part 3b a stabilizer 4 ensuring its stabilization on trajectory. The very structure of the indenter 3 will be described later.

Le sabot porte une ceinture 5, réalisée en matière plastique, et qui assure l'étanchéité aux gaz propulsifs lors du tir dans le tube d'une arme (non représenté).The sabot carries a belt 5, made of plastic material, and which seals against propellant gases during firing in the barrel of a weapon (not shown).

Lors du tir, les gaz du chargement propulsif (non représenté) exercent leur poussée au niveau d'une partie arrière 6 du sabot qui est au calibre et qui constitue ce qu'on appelle la plaque de poussée.During firing, the gases of the propellant charge (not shown) exert their thrust at the level of a rear part 6 of the sabot which is in the caliber and which constitutes what is called the thrust plate.

Une telle configuration générale d'un projectile sous calibré stabilisé par empennage (projectile flèche) est bien connue. On pourra notamment considérer les brevets FR-2521717 et FR-2661739 qui décrivent des projectiles flèches connus.Such a general configuration of a fin-stabilized subcaliber projectile (arrow projectile) is well known. In particular, we can consider patents FR-2521717 And FR-2661739 which describe known arrow projectiles.

Le sabot 2 est destiné à permettre le tir du projectile dans l'arme. Il est constitué de plusieurs segments (le plus souvent trois) qui entourent le pénétrateur3 et qui sont en contact deux à deux au niveau de plans de joints.Sabot 2 is intended to allow the projectile to be fired in the weapon. It is made up of several segments (most often three) which surround the indenter3 and which are in contact two by two at the joint planes.

A la sortie du tube de l'arme, les segments du sabot 2 s'écartent du pénétrateur 3 sous l'action de la pression aérodynamique qui s'exerce au niveau de la partie avant (AV) du sabot 2.At the exit from the barrel of the weapon, the segments of the sabot 2 deviate from the penetrator 3 under the action of the aerodynamic pressure which is exerted at the level of the front part (AV) of the sabot 2.

L'écartement des segments conduit à la rupture de la ceinture 5 et le sabot libère donc le pénétrateur 3 qui poursuit sa trajectoire.The separation of the segments leads to the rupture of the belt 5 and the sabot therefore releases the penetrator 3 which continues its trajectory.

Des moyens à concordance de forme (non représentés), par exemple un filetage, sont interposés entre le sabot 2 et le pénétrateur 3 pour assurer l'entraînement de ce dernier.Shape-matching means (not shown), for example a thread, are interposed between the sabot 2 and the indenter 3 to drive the latter.

La figure 2 montre de façon plus précise la structure du pénétrateur 3 qui comporte une partie centrale ou coeur 7 qui est entourée d'une gaine périphérique 8.There figure 2 shows more precisely the structure of the penetrator 3 which comprises a central part or core 7 which is surrounded by a peripheral sheath 8.

Conformément à l'invention, le coeur est formé d'un alliage comprenant de 85% à 97% en masse de tungstène et la gaine est réalisée en un alliage comprenant de 30% à 72% en masse de tungstène.In accordance with the invention, the core is formed from an alloy comprising from 85% to 97% by weight of tungsten and the sheath is made from an alloy comprising from 30% to 72% by weight of tungsten.

Le tungstène est allié, tant au niveau du coeur que de la gaine, à des métaux d'addition comme le Nickel qui sera toujours associé au Cobalt avec ou sans fer.Tungsten is alloyed, both at the level of the core and of the sheath, with addition metals such as Nickel which will always be associated with Cobalt with or without iron.

Plus précisément et en référence à la figure 3, au niveau du coeur 7, le matériau comprend des nodules 9 de tungstène de phase α à structure cristalline cubique centré qui sont liés entre eux par une matrice 10 d'une phase gamma γC associant le tungstène au Nickel, au cobalt avec ou sans fer (Fe), avec une structure cristalline cubique à face centrée.More specifically and with reference to the picture 3 , at the level of the core 7, the material comprises nodules 9 of phase α tungsten with a centered cubic crystalline structure which are bonded together by a matrix 10 of a gamma γ C phase combining tungsten with nickel, with cobalt with or without iron (Fe), with a face-centered cubic crystal structure.

Le taux de tungstène du coeur est compris entre 85% et 97%, ce qui conduit à une densité du coeur de l'ordre de 17 g/cm3. Le coeur 7 est formulé de façon à avoir une limite élastique supérieure ou égale à 1100 MPa (Méga Pascals). La ductilité est de l'ordre de 6% et sa résilience Charpy (essai non entaillé selon norme ISO 179-1 est de 80 J/cm2.The tungsten content of the core is between 85% and 97%, which results in a core density of the order of 17 g/cm 3 . The core 7 is formulated so as to have an elastic limit greater than or equal to 1100 MPa (Mega Pascals). The ductility is around 6% and its Charpy resilience (unnotched test according to ISO 179-1 standard) is 80 J/cm 2 .

La composition du cœur comportera (proportions en masse):

  • 85 à 97% de tungstène,
  • 1 à 10% de Nickel,
  • 1 à 6% de Cobalt.
The composition of the heart will include (proportions by mass):
  • 85 to 97% tungsten,
  • 1 to 10% Nickel,
  • 1 to 6% Cobalt.

Selon un autre mode de réalisation, la composition du coeur comportera (proportions en masse) :

  • 85 à 97% de tungstène,
  • 1 à 10% de Nickel,
  • 0.5 à 10% de Fer,
  • 1 à 8% de Cobalt.
According to another embodiment, the composition of the core will comprise (proportions by mass):
  • 85 to 97% tungsten,
  • 1 to 10% Nickel,
  • 0.5 to 10% Iron,
  • 1 to 8% Cobalt.

En référence à la figure 4, au niveau de la gaine 8, le matériau comprend essentiellement une matrice 11 d'une phase gamma γG associant essentiellement le tungstène au Nickel et au Cobalt avec ou sans Fe, et avec une structure cristalline cubique à face centrée qui est le signe que cette gaine a une haute résilience.With reference to the figure 4 , at the level of the sheath 8, the material essentially comprises a matrix 11 of a gamma γ G phase essentially associating tungsten with Nickel and Cobalt with or without Fe, and with a face-centered cubic crystalline structure which is the sign that this sheath has a high resilience.

Le pourcentage de tungstène de la gaine 8 est compris entre 30% et 72%, ce qui conduit à une densité de cette gaine qui peut varier entre 10 g/cm3 et 15 g/cm3. L'alliage de la gaine 8 sera formulé de façon à avoir une ductilité supérieure à 7% et une résilience élevée : résilience Charpy (essai non entaillé selon norme ISO 179-1) supérieure ou égale à 200 J/cm2.The percentage of tungsten of the sheath 8 is between 30% and 72%, which leads to a density of this sheath which can vary between 10 g/cm3 and 15 g/cm3. The alloy of the sheath 8 will be formulated so as to have a ductility greater than 7% and a high resilience: Charpy resilience (non-notched test according to standard ISO 179-1) greater than or equal to 200 J/cm 2 .

La composition de la gaine comportera (proportions en masse) :

  • 30 à 72% de tungstène,
  • 20 à 44% de Nickel,
  • 5 à 25% de Cobalt.
The composition of the sheath will include (proportions by mass):
  • 30 to 72% tungsten,
  • 20 to 44% Nickel,
  • 5 to 25% Cobalt.

Selon un autre mode de réalisation, la composition de la gaine comportera (proportions en masse):

  • 30 à 72% de tungstène,
  • 30 à 44% de Nickel,
  • 0.5 à 10% de Fer,
  • 5 à 25% de Cobalt.
According to another embodiment, the composition of the sheath will comprise (proportions by mass):
  • 30 to 72% tungsten,
  • 30 to 44% Nickel,
  • 0.5 to 10% Iron,
  • 5 to 25% Cobalt.

Etant donné la différence de concentration du tungstène dans la gaine et le coeur, la gaine 8 est donc plus ductile que le cœur 7.Given the difference in concentration of tungsten in the sheath and the core, the sheath 8 is therefore more ductile than the core 7.

Si la phase gamma γC du coeur associe le tungstène au nickel et au cobalt (avec ou sans Fer), la phase gamma γG de la gaine comportera aussi le nickel et :le cobalt (avec ou sans Fer) comme métaux additionnels.If the gamma γ C phase of the core combines tungsten with nickel and cobalt (with or without iron), the gamma γ G phase of the cladding will also include nickel and cobalt (with or without iron) as additional metals.

Les figures 5a et 5b montrent qu'après mise en forme du pénétrateur 3, les matrices 10 et 11 du coeur 8 et de la gaine 7 (matrices formées par les phases gamma du coeur et de la gaine) sont reliées l'une à l'autre de façon continue sans zone de transition. On pourra en particulier se référer aux zones repérées par les flèches Z1 et Z2 (la figure 5b est à un grossissement double de celui de la figure 5a). Il est clair sur les figures 5a et 5b que les phases gamma du coeur et de la gaine s'inter pénètrent et qu'il n'y a donc pas avec l'invention de zone de transition comme décrite par le brevet EP-1940574 .THE figures 5a and 5b show that after shaping the indenter 3, the matrices 10 and 11 of the core 8 and of the sheath 7 (matrices formed by the gamma phases of the core and of the sheath) are connected to each other in a continuous manner without transition zone. In particular, reference may be made to the zones marked with the arrows Z1 and Z2 (the figure 5b is at twice the magnification of the figure 5a ). He is clear on the figures 5a and 5b that the gamma phases of the core and of the cladding interpenetrate and that there is therefore no transition zone with the invention as described by the patent EP-1940574 .

Il en résulte une liaison intime de la gaine 7 sur le coeur 8 et une résistance extrêmement forte de cette liaison.This results in an intimate connection of the sheath 7 on the core 8 and an extremely strong resistance of this connection.

Pour réaliser un tel pénétrateur 3 on met en oeuvre un procédé décrit de la façon suivante :
Au cours d'une étape A, pour fabriquer un alliage comprenant de 85% à 97% en masse de tungstène, les poudres de Tungstène, Nickel, Cobalt et éventuellement de Fer sont mélangées de façon homogène et pré comprimés sous forme d'un barreau qui constituera le coeur.To produce such an indenter 3, a process described as follows is implemented:
During a step A, to manufacture an alloy comprising 85% to 97% by mass of tungsten, the powders of Tungsten, Nickel, Cobalt and possibly Iron are mixed homogeneously and pre-compressed in the form of a bar. which will constitute the heart.

Au cours d'une étape B, on élabore une gaine 8 d'un alliage comprenant de 30% à 72% en masse de tungstène associé à des métaux additionnels comprenant le Nickel, le Cobalt et éventuellement du Fer.During a step B, a sheath 8 of an alloy comprising 30% to 72% by mass of tungsten associated with additional metals comprising nickel, cobalt and optionally iron is produced.

Les matériaux sont mélangés de façon homogène puis comprimés dans un outillage qui comporte un noyau cylindrique ayant un diamètre égal ou supérieur au diamètre interne souhaité pour la gaine. Le reste de l'outillage de compression est classique.The materials are mixed homogeneously and then compressed in a tool which comprises a cylindrical core having a diameter equal to or greater than the internal diameter desired for the sheath. The rest of the compression tooling is conventional.

Au cours d'une étape C on assemble par frittage la gaine et le coeur.During a step C, the cladding and the core are assembled by sintering.

Le frittage a lieu en présence de phase liquide. On pourra mettre en oeuvre le procédé de frittage à haute puissance décrit dans la demande de brevet WO03/027340 et qui met en oeuvre un chauffage par induction.Sintering takes place in the presence of a liquid phase. The high-power sintering process described in the application for patent WO03/027340 and which uses induction heating.

Les alliages sont consolidés à des températures comprises entre 1400°C et 1600°C.The alloys are consolidated at temperatures between 1400°C and 1600°C.

Le frittage permet d'assurer la continuité des phases gamma entre la gaine et le coeur.The sintering makes it possible to ensure the continuity of the gamma phases between the cladding and the core.

Ces étapes A à C conduisent ainsi à la réalisation d'un ébauché du pénétrateur.These steps A to C thus lead to the production of a rough outline of the indenter.

On procède ensuite aux différents usinages de l'ébauché permettant de réaliser le pénétrateur 3 souhaité. On réalisera en particulier le filetage externe porté par la gaine et permettant l'assemblage du pénétrateur 3 et de son sabot de lancement 2.One then proceeds to the various machining operations of the blank making it possible to produce the desired indenter 3. In particular, the external thread carried by the sheath and allowing the assembly of the penetrator 3 and its launching shoe 2.

On pourra réaliser des gaines dont le diamètre est compris entre 1,4 et 2,0 fois le diamètre du coeur. L'épaisseur de la gaine 8 pourra ainsi varier entre 5 mm et 9mm pour un pénétrateur de 35 mm de diamètre externe.It will be possible to produce claddings whose diameter is between 1.4 and 2.0 times the diameter of the core. The thickness of the sheath 8 may thus vary between 5 mm and 9 mm for an indenter with an external diameter of 35 mm.

A titre d'exemple, on a ainsi fabriqué les pénétrateurs suivants :By way of example, the following penetrators have thus been manufactured:

Exemple 1Example 1

Diamètre du coeur égal à 0,5-0,7 fois le diamètre de la gaine.Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.

Le coeur est formé de 85% en masse de tungstène, et ayant une densité de 16,5 g/cm3, une limite élastique de 1 800 MPa, une ductilité de 10% et une résilience Charpy non entaillé de 150 J/cm2.The core is formed of 85% by mass of tungsten, and having a density of 16.5 g/cm 3 , an elastic limit of 1800 MPa, a ductility of 10% and an unnotched Charpy resilience of 150 J/cm 2 .

L'alliage du coeur comprend 85% en masse de Tungstène, 15% en masse de Nickel et 5% en masse de Cobalt.The core alloy comprises 85% by mass of Tungsten, 15% by mass of Nickel and 5% by mass of Cobalt.

La gaine a une densité de 11,2 g/cm2, une limite élastique de 1 400 MPa, une ductilité de 18% et une résilience Charpy non entaillée de 400 J/cm2. L'alliage de la gaine comprend (proportions en masse) : 38,0% de Tungstène, 40% de Nickel et 22% de Cobalt.The sheath has a density of 11.2 g/cm 2 , an elastic limit of 1400 MPa, a ductility of 18% and an unnotched Charpy resilience of 400 J/cm 2 . The sheath alloy comprises (proportions by mass): 38.0% Tungsten, 40% Nickel and 22% Cobalt.

Ce pénétrateur (et son ébauché) a été fabriqué en mettant en œuvre le procédé précédemment décrit.This penetrator (and its blank) was manufactured by implementing the process described above.

Exemple 2Example 2

Diamètre du coeur égal à 0,5-0,7 fois le diamètre de la gaine.Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.

Le coeur est formé de 89% en masse de tungstène, et ayant une densité de 17,1 g/cm3, une limite élastique de 1 500 MPa, une ductilité de 9% et une résilience Charpy non entaillé de 300 J/cm2. L'alliage du coeur comprend 89% en masse de Tungstène, 7,5% en masse de Nickel et 3,5% en masse de Cobalt.The core is formed of 89% by mass of tungsten, and having a density of 17.1 g/cm 3 , an elastic limit of 1500 MPa, a ductility of 9% and an unnotched Charpy resilience of 300 J/cm 2 . The core alloy comprises 89% by mass of Tungsten, 7.5% by mass of Nickel and 3.5% by mass of Cobalt.

La gaine est formée de 68% en masse de tungstène et ayant une densité de 14,1 g/cm2, une limite élastique de 2 000 MPa, une ductilité de 11% et une résilience Charpy non entaillée de 400 J/cm2. L'alliage de la gaine comprend (proportions en masse) : 68% de Tungstène, 22% de Nickel et 10% de Cobalt.The sheath is formed of 68% by mass of tungsten and having a density of 14.1 g/cm 2 , an elastic limit of 2000 MPa, a ductility of 11% and an unnotched Charpy resilience of 400 J/cm 2 . The sheath alloy comprises (proportions by mass): 68% Tungsten, 22% Nickel and 10% Cobalt.

Ce pénétrateur (et son ébauché) a été fabriqué en mettant en oeuvre le procédé précédemment décrit.This penetrator (and its blank) was manufactured by implementing the process described above.

Exemple 3Example 3

Diamètre du cœur égal à 0,5-0,7 fois le diamètre de la gaine.Diameter of the core equal to 0.5-0.7 times the diameter of the sheath.

Le coeur est formé de 95% en masse de tungstène, et ayant une densité de 18,3 g/cm3, une limite élastique de 1 300 MPa, une ductilité de 7% et une résilience Charpy non entaillée de 50 J/cm2. L'alliage du coeur comprend 95% en masse de Tungstène, 2% en masse de nickel, 1,5% en masse de cobalt et 2% en masse de fer.The core is formed of 95% by mass of tungsten, and having a density of 18.3 g/cm 3 , an elastic limit of 1300 MPa, a ductility of 7% and an unnotched Charpy resilience of 50 J/cm 2 . The core alloy comprises 95% by mass of Tungsten, 2% by mass of nickel, 1.5% by mass of cobalt and 2% by mass of iron.

La gaine est formée de 70,0% en masse de tungstène et ayant une densité de 14,0 g/cm2, une limite élastique de 2000 MPa, une ductilité de 9% et une résilience Charpy non entaillé de 300 J/cm2. L'alliage de la gaine comprend (proportions en masse) : 70,0% en masse de Tungstène, 18% en masse de Nickel, 10% en masse de Cobalt et 2% en masse de Fe.The sheath is formed of 70.0% by mass of tungsten and having a density of 14.0 g/cm 2 , an elastic limit of 2000 MPa, a ductility of 9% and an unnotched Charpy resilience of 300 J/cm 2 . The sheath alloy comprises (proportions by mass): 70.0% by mass of Tungsten, 18% by mass of Nickel, 10% by mass of Cobalt and 2% by mass of Fe.

Ce pénétrateur (et son ébauché) a été fabriqué en mettant en oeuvre le procédé précédemment décrit.This penetrator (and its blank) was manufactured by implementing the process described above.

Claims (6)

  1. A heavy metal penetrator (3) with a high tungsten content incorporating a central part or core (7) formed of an alloy comprising from 85% to 97% by mass of tungsten associated with additional metals and which is surrounded by a peripheral sheath (8) made of a more ductile tungsten alloy than that of the core (7), penetrator characterized in that the sheath (8) is made of an alloy comprising 30% to 72% by mass of tungsten, the core (7) comprising nodules (9) of tungsten bound in a matrix (10) of a gamma phase γC associating tungsten with additional metals, the two gamma phases being continuously joined to one another with no transition zone.
  2. A heavy metal penetrator according to Claim 1, characterized in that the gamma phases of the core γC and of the sheath γG have a composition associating tungsten, nickel, cobalt and possibly iron.
  3. A heavy metal penetrator according to Claim 2, characterized in that the core (7) comprises 85% by mass of tungsten and the sheath (8) 38% by mass of tungsten, the gamma phases of the core Yc and the sheath γG being of compositions associating tungsten, nickel and cobalt.
  4. A heavy metal penetrator according to Claim 2, characterized in that the core (7) comprises 89% by mass of tungsten and the sheath (8) 68% by mass of tungsten, the gamma phases of the core Yc and the sheath γG having compositions associating tungsten, nickel and cobalt.
  5. A heavy metal penetrator according to Claim 2, characterized in that the alloy making up the core (7) comprises 95% by mass of tungsten, 2% by mass of nickel, 1.5% by mass of cobalt and 2% by mass of iron and the sheath (8) 70% by mass of tungsten, the gamma phases of the core Yc and the sheath γG having compositions associating tungsten, nickel, cobalt and iron.
  6. A process to manufacture a heavy metal penetrator with a high tungsten content according to one of Claims 1 to 5, characterized in that it comprises the following steps:
    - production of a core (7) composed of compacted powders comprising from 85% to 97% by mass of tungsten associated with additional material comprising nickel, cobalt with or without iron,
    - production of a sheath (8) composed of compacted powders comprising from 30% to 72% by mass of tungsten associated with additional metals comprising nickel, cobalt with or without iron,
    - assembly by sintering of the sheath (8) and core (7).
EP16757687.5A 2015-07-22 2016-07-20 Penetrator comprising a core surrounded by a ductile sheath and process for manufacturing such a penetrator Active EP3349929B1 (en)

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FR1501552A FR3039266B1 (en) 2015-07-22 2015-07-22 PENETRATOR HAVING A CORE SURROUNDED BY A DUCTILE SHEATH AND METHOD FOR MANUFACTURING SUCH A PENETRATOR
PCT/FR2016/000122 WO2017013314A1 (en) 2015-07-22 2016-07-20 Penetrator comprising a core surrounded by a ductile sheath and process for manufacturing such a penetrator

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IL256732A (en) 2018-03-29
IL256732B (en) 2021-04-29
FR3039266A1 (en) 2017-01-27
US20180231358A1 (en) 2018-08-16
ES2963820T3 (en) 2024-04-02
US10240906B2 (en) 2019-03-26
CN107848036B (en) 2020-04-14
PL3349929T3 (en) 2024-05-20
EP3349929C0 (en) 2023-09-06
CN107848036A (en) 2018-03-27
FR3039266B1 (en) 2017-09-01
EP3349929A1 (en) 2018-07-25
KR102203134B1 (en) 2021-01-14
HUE064184T2 (en) 2024-02-28
WO2017013314A1 (en) 2017-01-26
KR20180033244A (en) 2018-04-02

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