阅读说明：本技术 含强韧外层及脆性内层的复合含能破片及其制备方法 (Composite energetic fragment containing tough outer layer and brittle inner layer and preparation method thereof ) 是由 束庆海 石艳松 吕席卷 成丽荣 赵帅 王东旭 邹浩明 徐博林 文萍 夏为浩 于 2021-08-18 设计创作，主要内容包括：本发明公开了含强韧外层及脆性内层的复合含能破片及其制备方法,所述制备方法包括：获得包括钨锆合金的内层材料；将铝金属粉末、镍金属粉末和增强材料粉末的混合球磨粉填充于所述内层材料外,进行共模压及共烧结,得到所述复合含能破片,本发明的制备方法过程简单、生产成本低,所得复合含能破片具有高强高韧性的外层和高脆性的内层,具有很高的侵彻和二次毁伤效能。(The invention discloses a composite energetic fragment containing a tough outer layer and a brittle inner layer and a preparation method thereof, wherein the preparation method comprises the following steps: obtaining an inner layer material comprising a tungsten-zirconium alloy; the preparation method has the advantages of simple process and low production cost, and the obtained composite energetic fragment has an outer layer with high strength and high toughness and an inner layer with high brittleness, and has very high penetration and secondary damage efficiency.)

1. The preparation method of the composite energetic fragment containing the tough outer layer and the brittle inner layer is characterized by comprising the following steps:

obtaining an inner layer material of the energetic fragment, wherein the inner layer material comprises an alloy of tungsten metal and zirconium metal;

and filling mixed ball milling powder obtained by mixing and ball milling aluminum metal powder, nickel metal powder and reinforcing material powder outside the inner layer material, and performing co-die pressing and co-sintering together to obtain the composite energy-containing broken chip.

2. The method for preparing the composite material according to claim 1, wherein the preparing of the inner layer material comprises:

mixing and ball-milling tungsten metal powder and zirconium metal powder to obtain bimetal mixed powder;

adding a binder solution into the bimetal mixed powder, and performing binding granulation;

and pre-pressing and pre-sintering the mixture particles obtained after granulation to obtain the inner layer material.

3. The method of claim 2, wherein: the mass of the tungsten metal powder is 30-70% of that of the bimetal mixed powder.

4. The method of claim 2, wherein: the mixing and ball-milling time of the tungsten metal powder and the zirconium metal powder is 1-5 h; and/or the pre-pressing pressure is 10-50 MPa, and/or the pre-pressing time is 1-10 min; and/or the pre-sintering temperature is 1250-1550 ℃, and/or the pre-sintering time is 2-4 h.

5. The method of claim 2, wherein: the binder solution is selected from a polyvinyl alcohol solution with the mass percentage concentration of 1-10 wt%.

6. The method of claim 1, wherein: the mass of the aluminum metal powder is 20-60% of that of the mixed ball milling powder, and/or the mass ratio of the aluminum metal powder, the nickel metal powder and the reinforcing material powder in the mixed ball milling powder is (1-10): 3-15): 1.

7. The method of claim 1, wherein: the reinforcing material is selected from tungsten metal and/or tantalum metal.

8. The method of claim 1, wherein: the pressure of the co-molding is 10-50 MPa; and/or the co-sintering temperature is 450-550 ℃, and/or the co-sintering time is 0.5-2 h.

9. The method of claim 1, wherein: the mass ratio of the inner layer material to the mixed ball milled powder is (1-5): 5.

10. the composite energetic fragment prepared by the preparation method of any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of metal-based composite energetic fragments.

Background

The tungsten alloy fragment is increasingly widely used as a killing element for killing ammunition due to high density, high speed keeping and high armor piercing capacity, and meanwhile, according to the requirement of ammunition tactical use, the fragment can meet the armor piercing power, is expected to have the functions of ignition or pilot fire, and can have higher secondary damage area and after-damage effect after armor piercing, so that the single tungsten-zirconium composite energetic fragment with the function can be produced at one time.

The aluminum-nickel alloy is a typical energetic structural material, is quite stable at room temperature, and has higher strength and plasticity, and the tungsten-zirconium alloy has higher brittleness. Under the action of impact load, the Al-Ni alloy and W-Zr alloy will produce chemical reaction to release great amount of heat. The composite energetic fragment prepared by the characteristic can utilize the high toughness of the aluminum-nickel alloy fragment to penetrate through a target, can also utilize the fragility of the tungsten-zirconium alloy to form a fragment cloud bullet screen behind the target, generates an additional damage effect on the target behind the target by combining the energy release characteristic of the tungsten-zirconium alloy, and finally obviously improves the damage efficiency.

However, the penetration capability and the secondary damage capability of the aluminum-nickel series or tungsten-zirconium series metal energetic fragments in the prior art are still insufficient, and meanwhile, the preparation method is complex, the production cost is high, and the new military application requirements under complex environments cannot be met.

Disclosure of Invention

The invention aims to provide a preparation method capable of further improving penetration and secondary damage performance of an aluminum-nickel-tungsten-zirconium composite energetic fragment, and the preparation method is simple in process, free of special process requirements and low in production cost, and the obtained composite energetic fragment has an outer layer with high strength and high toughness and an inner layer with high brittleness.

The invention firstly provides the following technical scheme:

the preparation method of the composite energetic fragment containing the tough outer layer and the brittle inner layer comprises the following steps:

obtaining an inner layer material of the energetic fragment, wherein the inner layer material comprises an alloy of tungsten metal and zirconium metal;

and filling mixed ball milling powder obtained by mixing and ball milling aluminum metal powder, nickel metal powder and reinforcing material powder outside the inner layer material, and performing co-die pressing and co-sintering to obtain the composite energy-containing broken chip.

According to some preferred embodiments of the invention, the preparation of the inner layer material comprises:

mixing and ball-milling tungsten metal powder and zirconium metal powder to obtain bimetal mixed powder;

adding a binder solution into the bimetal mixed powder, and performing binding granulation;

and pre-pressing and pre-sintering the mixture particles obtained after granulation to obtain the inner layer material.

According to some preferred embodiments of the present invention, the mass of the tungsten metal powder is 30 to 70% of the mass of the bimetal mixed powder.

According to some preferred embodiments of the present invention, the mixing and ball-milling of the tungsten metal powder and the zirconium metal powder is performed for 1 to 5 hours.

According to some preferred embodiments of the present invention, the pre-pressing pressure is 10 to 50 MPa.

According to some preferred embodiments of the present invention, the pre-pressing time is 1 to 10 min.

According to some preferred embodiments of the present invention, the temperature of the pre-sintering is 1250 to 1550 ℃.

According to some preferred embodiments of the present invention, the pre-sintering time is 2 to 4 hours.

According to some preferred embodiments of the present invention, the binder solution is selected from low melting point adhesive polymer materials such as 1 wt% to 10 wt% polyvinyl alcohol solution.

According to some preferred embodiments of the present invention, the mass of the aluminum metal powder is 20 to 60% of the mass of the mixed ball mill powder.

According to some preferred embodiments of the present invention, in the mixed ball mill powder, the mass ratio of the aluminum metal powder, the nickel metal powder and the reinforcing material powder is (1-10): (3-15): 1.

According to some preferred embodiments of the invention, the reinforcing material is selected from heavy metals such as W, Ta and the like.

According to some preferred embodiments of the present invention, the co-molding pressure is 10 to 50 MPa.

According to some preferred embodiments of the present invention, the co-sintering temperature is 450-550 ℃, and/or the co-sintering time is 0.5-2 h.

According to some preferred embodiments of the invention, the mass ratio of the inner layer material to the mixed ball milled powder is (1-5): 5.

the invention further provides the composite energetic fragment prepared by any one of the preparation methods.

The combination of the inner layer and the outer layer of the composite energetic fragment replaces the existing clearance fit mode, the tungsten-zirconium alloy of the inner layer and the aluminum-nickel alloy of the outer layer realize alloying combination, the integral molding is realized, no obvious interface layer exists, the combination is tight, and the integral strong plasticity and the penetration reaction effect are ensured.

The invention has the following beneficial effects:

in the composite energetic fragment prepared by the invention, the high-brittleness tungsten-zirconium alloy is coated by the high-toughness aluminum-nickel energetic material, the outer layer material has low density, good activity, high strength and good plasticity, and has penetration and hole expansion capabilities, the inner layer material is easy to crush to form a fragment cloud bullet screen, and the composite energetic fragment can be subjected to gradient charge design and integrated processing, has high efficiency and simple processing preparation process compared with a split composite structure, and is easy to realize engineering application;

compared with a single tungsten-zirconium system fragment, the composite energetic fragment prepared by the invention has higher toughness as a whole, has obvious penetration and hole expansion effects, and has remarkably improved penetration and explosion power through a target range test;

in the composite energy-containing fragment prepared by the invention, the tungsten-zirconium alloy fragment at the inner layer can generate chemical reaction under the action of impact load to release huge energy, and after the tungsten-zirconium alloy fragment and the aluminum-nickel intermetallic reaction release heat are cooperated, the activity is higher, the fragment cloud barrage is larger, and the secondary damage effect is obviously improved;

the preparation method of the invention adopts conventional metal powder such as tungsten powder, zirconium powder, aluminum powder and the like, can be implemented through powder mixing, mould pressing, pre-sintering, sintering processes and the like, has simple process, no special process requirements and low cost, and is convenient for batch production.

Drawings

FIG. 1 is a graph showing the comprehensive damage effect of the composite energetic fragment obtained in example 1 impacting a composite target plate at an initial velocity of 1050m/s, wherein (a) is a graph showing the effect of a front target plate and (b) is a graph showing the effect of a rear target plate;

FIG. 2 is a graph showing the comprehensive damage effect of the composite energetic fragment obtained in example 2 impacting a target plate at an initial speed of 1300 m/s;

FIG. 3 is a diagram showing the comprehensive damage effect of the composite energetic fragment obtained in example 3 after striking and igniting an aviation kerosene fuel tank at a primary speed of 1300 m/s.

Detailed Description

The present invention is described in detail below with reference to the following embodiments and the attached drawings, but it should be understood that the embodiments and the attached drawings are only used for the illustrative description of the present invention and do not limit the protection scope of the present invention in any way. All reasonable variations and combinations that fall within the spirit of the invention are intended to be within the scope of the invention.

According to the technical scheme of the invention, the specific preparation method of the composite energetic fragment comprises the following steps:

the method comprises the following steps: placing tungsten powder and zirconium powder in an all-directional planetary ball mill to be uniformly mixed, wherein the mass of the tungsten powder is 30-70% of the total mass of the tungsten powder and the zirconium powder;

step two: adding a prepared binder solution into the uniform powder obtained in the step one, and performing binding granulation;

step three: placing the granulated metal obtained in the step two in a pressing die, and performing prepressing molding;

step four: pre-sintering the pre-pressed forming piece obtained in the third step to obtain a product A;

step five: putting the aluminum powder, the nickel powder and the reinforcement powder into an all-dimensional planetary ball mill, and uniformly mixing, wherein the mass of the aluminum powder is 20-60% of the total mass of the aluminum powder, the nickel powder and the reinforcement powder;

step six: filling the product A obtained in the fourth step and the mixed powder obtained in the fifth step into a mold cavity from inside to outside according to the mass ratio, and performing compression molding;

step seven: and sintering the pressed compact sample obtained in the step six to obtain the composite energy-containing fragment.

Among them, some preferred modes are as follows:

the mixing time of the first step and the fifth step is 1-5 h.

And thirdly, pre-pressing pressure of 10-50 MPa, and pre-pressing time of 1-10 min.

And fourthly, the pre-sintering temperature is 1250-1550 ℃, and the pre-sintering time is 2-4 h.

And seventhly, sintering at the temperature of 450-550 ℃ for 0.5-2 h.

The binder solution in the second step is selected from 1 wt% -10 wt% of polyvinyl alcohol solution.

And fifthly, selecting the reinforcing body from W powder or Ta powder with the particle size of 1-10 microns.

Sixthly, the mass ratio is (1-5): 5.

example 1

The composite energetic fragment containing the tough outer layer and the brittle inner layer is prepared by the following steps:

weighing and mixing powder:

weighing 30g of tungsten powder and 70g of zirconium powder according to the mass ratio of the tungsten powder to the zirconium powder of 30/70, placing the tungsten powder and the zirconium powder into an all-directional planetary ball mill for mixing for 1 hour, adding 2 wt% of polyvinyl alcohol binder solution after uniformly mixing, and performing binding granulation;

pre-pressing:

placing the mixture obtained after granulation in a cylindrical mold for compression, pressurizing at a pressurizing rate of 30N/s until the pressure intensity is 30MPa, maintaining the pressure for 3min, then relieving the pressure at a pressure relieving rate of 30N/s, and demolding after pressure relief to obtain a pre-pressing piece;

pre-sintering:

placing the obtained prepressing piece in a vacuum high-temperature sintering furnace to be sintered under the argon atmosphere, wherein the sintering temperature is 1450 ℃, and the sintering time is 2 hours, so as to obtain a cylindrical test piece A;

weighing and mixing powder:

weighing 30g of micron-sized aluminum powder, 65g of nickel powder and 15g of tungsten powder according to the mass ratio of Al powder/Ni powder/reinforcing powder of 30/55/15, and mixing in an omnibearing planetary ball mill for 1 h;

die pressing and sintering:

mixing the obtained product A with the mixed powder obtained in the step five according to the mass ratio of 1: and 5, adding a test piece A into the center of a cubic mold with the side length of 8mm, filling the mixed powder outside the test piece A into a cubic mold cavity, performing compression molding under a full-automatic sample press with the compression pressure of 20MPa, and sintering the obtained compression blank at 450 ℃ for 2 hours in a vacuum or high-temperature atmosphere furnace to obtain the composite energy-containing broken piece.

The density of the composite energetic fragment with the outer layer of the Al-Ni series and the inner layer of the W-Zr series prepared in the embodiment is about 5.8g/cm³(ii) a The strength limit of the alloy is about 1800MPa at the strain rate of 1000/s; under a quasi-static compression test, the strength of the product is about 1200 MPa; when the composite target plate is impacted by a Q235 steel plate with the thickness of 6mm and an aluminum plate with the thickness of 2mm at the initial speed of 1050m/s, deflagration occurs, the deflagration penetrates through the front target plate to form a regular through hole with the diameter of about 14-16 mm, and a large-area damage effect is formed on the rear target plate, which are respectively shown in the attached figures 1(a) and (b).

Example 2

The composite energetic fragment containing the tough outer layer and the brittle inner layer is prepared by the following steps:

weighing and mixing powder:

weighing 50g of tungsten powder and 50g of zirconium powder according to the mass ratio of the tungsten powder to the zirconium powder of 50/50, placing the tungsten powder and the zirconium powder in an all-directional planetary ball mill for mixing for 1 hour, and bonding and granulating after uniformly mixing;

pre-pressing:

placing the obtained granules in a cylindrical die for compression, pressurizing at a pressurizing rate of 30N/s until the pressure intensity is 30MPa, maintaining the pressure for 5min, then relieving the pressure at a pressure relieving rate of 30N/s, and demolding after pressure relief to obtain a molded part;

pre-sintering:

placing the molded piece in a sintering furnace for sintering, wherein an argon atmosphere is used in the sintering process, the sintering temperature is 1500 ℃, and the sintering time is 1h, so that a cylindrical test piece A is obtained;

weighing and mixing powder:

weighing 30g of micron-sized aluminum powder, 55g of nickel powder and 15g of tungsten powder according to the mass ratio of Al powder/Ni powder/reinforcing powder of 30/55/15, and mixing in an omnibearing planetary ball mill for 1 h;

die pressing and sintering:

mixing the obtained product A with the obtained mixed powder according to the mass ratio of 2: and 5, adding the test piece A into the center of a cylindrical die with the diameter of 10mm, filling the mixed powder outside the test piece A into a cylindrical die cavity, pressing and molding the mixture under a full-automatic sample pressing machine at the pressing pressure of 30MPa, and sintering the obtained pressed blank at 480 ℃ for 1.5h in a vacuum or high-temperature atmosphere furnace to obtain the composite energetic fragment.

The density of the composite energetic fragment prepared in this example was about 6.3g/cm³(ii) a Its strength limit at strain rate 1000/s is about 1900 MPa; the strength of the product in the quasi-static compression test is about 1300 MPa; the detonation of a 6mm thick EH36 steel plate hit at an initial velocity of 1300m/s resulted in regular through holes of about 20mm diameter, as shown in figure 2.

Example 3

The composite energetic fragment containing the tough outer layer and the brittle inner layer is prepared by the following steps:

weighing and mixing powder:

weighing 70g of tungsten powder and 30g of zirconium powder according to the mass ratio of the tungsten powder to the zirconium powder of 70/30, placing the tungsten powder and the zirconium powder in an all-directional planetary ball mill for mixing for 1 hour, and granulating after mixing uniformly;

pre-pressing:

placing the granules in a cylindrical die for compression, pressurizing at a pressurizing rate of 20N/s until the pressure intensity is 20MPa, maintaining the pressure for 2min, then relieving the pressure at a pressure relieving rate of 20N/s, and demolding after pressure relief to obtain a molded part;

pre-sintering:

placing the molded piece in a sintering furnace for sintering, wherein an argon atmosphere is used in the sintering process, the sintering temperature is 1500 ℃, and the sintering time is 3 hours, so that a cylindrical test piece A is obtained;

weighing and mixing powder:

weighing 15g of micron-sized aluminum powder, 75g of nickel powder and 10g of reinforced Ta powder according to the mass ratio of Al powder/Ni powder/reinforced powder of 15/75/10, and placing the components in an omnibearing planetary ball mill for mixing for 2 hours;

die pressing and sintering:

mixing the obtained product A with the obtained mixed powder according to the mass ratio of 3: and 5, adding a test piece A into the center of a cylindrical die with the diameter of 10mm, filling the mixed powder outside the test piece A into a cylindrical die cavity, performing compression molding under a full-automatic sample press with the compression pressure of 50MPa, and sintering the obtained compression blank at 500 ℃ for 1h in a vacuum or high-temperature atmosphere furnace to obtain the composite energy-containing fragment.

The density of the composite energetic fragment prepared in this example was about 8.1g/cm³The strength limit at strain rate 1000/s is about 2200MPa and the strength in the quasi-static compression test is about 1500MPa, striking a tank containing jet fuel at a primary velocity of 1300m/s produces a pilot burn-out effect and produces irregular tear holes of about 20mm diameter, as shown in figure 3.

The above examples are merely preferred embodiments of the present invention, and the scope of the present invention is not limited to the above examples. All technical schemes belonging to the idea of the invention belong to the protection scope of the invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention, and such modifications and embellishments should also be considered as within the scope of the invention.