CN113201693B

CN113201693B - Bullet steel for penetration and killing of multifunctional warhead and preparation method thereof

Info

Publication number: CN113201693B
Application number: CN202110512093.6A
Authority: CN
Inventors: 王树山; 孙雨荟; 赵传; 刘东奇; 于开勇
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2021-05-11
Filing date: 2021-05-11
Publication date: 2022-03-25
Anticipated expiration: 2041-05-11
Also published as: CN113201693A

Abstract

The invention discloses a bullet steel for penetration and killing of a multifunctional warhead and a preparation method thereof, wherein the content of alloy elements such as Si, Mn, V, B, Cr and the like in carbon steel is adjusted, so that the strength of the existing bullet steel is ensured, the fragment rate of the bullet steel is improved, particularly the fragment rate of the bullet steel with the strength of about 1500MPa is improved, and the possibility is provided for the performance improvement of weaponry and the research and development of novel weaponry.

Description

Bullet steel for penetration and killing of multifunctional warhead and preparation method thereof

Technical Field

The invention belongs to the technical field of steel smelting, and particularly relates to elastic steel for penetration and killing of a multifunctional warhead and a preparation method thereof.

Background

In warhead design, the selection of the projectile material is an important ring in determining warhead power and destruction efficiency. In addition, due to the use requirements of severe launching conditions and special working environments, and the application of new generation of high-energy explosives, the development of elastomeric materials towards higher strength, ductility and toughness while ensuring excellent crushing effect is required.

The design in the penetration fighting part aims at the attack and hardness task, and the shell strength of the fighting part is emphasized, so that the shell material of the penetration fighting part is mainly high-strength high-toughness steel, and the shell material is generally called as bullet steel. The bullet steel is used for manufacturing a shell of a bullet (warhead), the shell is used as a force bearing component for keeping structural integrity and stabilizing internal filler in the process of launching, flying and penetration of the bullet, and the shell forms a natural fragment damage element under the action of an implosion load when acting on a target.

At present, the domestic common elastic steel comprises: DT300, TH200 and D6 AC. Among them, D6AC has the highest strength, the yield strength is 1500MPa, the elongation is 10%, and because the crushability of the materials is not considered in the development process, the crushability of the warhead made of the high-strength steels is poor.

However, the improvement of the level of the difficulty of the target destruction puts new demands on the fragment killing power of the deep penetration warhead, for example, the existing hard-attacking task needs to kill personnel or technical equipment in firmer work, and the traditional hard-attacking projectile basically has no fragment killing capability, so that the research on the projectile steel with both high strength and high fragment rate is urgently needed.

Disclosure of Invention

In view of the above, the invention provides the elastic steel for penetrating and killing the multifunctional warhead and the preparation method thereof, so that the elastic steel has excellent performances of high strength, high toughness and high fragment rate.

The invention provides a bullet steel for penetration and killing of a multifunctional warhead, which comprises the following chemical components in percentage by weight: c: 0.32-0.38%; si: 0.80-1.10%; mn: 0.95-1.25%; b: 0.010-0.015 percent; v: 0.04-0.06%; cr: 1.1-1.4%; the balance being Fe and unavoidable impurities.

The invention provides a preparation method of bullet steel for penetration and killing of a multifunctional warhead, which comprises the following steps:

the method comprises the steps of molten iron pre-desulfurization, converter smelting, deoxidation alloying, CAS stirring furnace external refining, secondary refining, forging, rough machining, hot stamping, quenching, tempering and finish machining.

Further, the heat preservation time for quenching is 50min-70min, the heating temperature is 880-900 ℃, and the cooling medium is oil.

Further, the tempering is carried out for 80-100 min at the heating temperature of 350-400 ℃ by using water as a cooling medium.

Further, KR molten iron is adopted for pre-desulfurization of the molten iron, and the content of sulfur is reduced to be lower than 0.002%.

Further, the converter smelting adopts a BOF method converter smelting, and oxygen top blowing is used for removing C.

Further, the rough machining is to machine the steel ingot into round-corner square steel with a certain size, and the surface roughness of the square steel is not lower than 3.2.

Has the advantages that:

1. according to the invention, by adjusting the contents of alloy elements such as Si, Mn, V, B, Cr and the like in the carbon steel, the strength of the existing bullet steel is ensured, the fragment rate of the bullet steel is increased, particularly the fragment rate of the bullet steel with the strength of about 1500MPa is increased, and the possibility is provided for the performance improvement of weaponry and the research and development of novel weaponry.

2. The invention improves the manufacturing process aiming at the components of the provided elastic steel, through heat treatment quenching and tempering treatment, the metallographic structure is mainly a tempered troostite structure, so that the yield strength of the formed elastic steel finished product is more than or equal to 1500MPa, the elongation is more than or equal to 10 percent, and the elastic steel has excellent performances of high strength, high toughness and high fragment rate.

Detailed Description

The present invention will be described in detail below with reference to examples.

The invention provides a bullet steel for penetration and killing of a multifunctional warhead, which comprises the following chemical components in percentage by weight: c: 0.32-0.38%; si: 0.80-1.10%; mn: 0.95-1.25%; b: 0.010-0.015 percent; v: 0.04-0.06%; cr: 1.1-1.4%; the balance of Fe and inevitable impurities.

The invention provides a preparation method of bullet steel for penetration and killing of a multifunctional warhead, which comprises the following steps: the method comprises the steps of molten iron pre-desulfurization, converter smelting, deoxidation alloying, CAS stirring furnace external refining, secondary refining, forging, rough machining, hot stamping, quenching, tempering, finish machining and the like to form a finished product. The above process specifically comprises the steps of:

step 1, pre-desulfurizing molten iron.

In the invention, the molten iron pre-desulfurization is completed by adopting a KR molten iron pretreatment mode, and the content of sulfur is reduced to be lower than 0.002 percent so as to prevent the sulfur from generating hot shortness.

And 2, smelting in a converter.

The invention adopts BOF method converter smelting, and oxygen top blowing is used for removing C.

And step 3, refining outside the CAS stirring furnace.

The invention adopts argon gas blowing and removes impurities through the isolation cover.

And 4, rough machining.

According to the size of the processed warhead, the steel ingot is processed into round-corner square steel with a certain size, and the surface roughness of the square steel is not lower than 3.2.

And 5, quenching.

The invention adopts the heat preservation time of 50min-70min, the heating temperature of 880-900 ℃, the cooling medium of oil, and fine and uniform martensite structure can be obtained after quenching.

And 6, tempering.

The invention adopts the heat preservation time of 80min-100min, the heating temperature is 350 ℃ to 400 ℃, the cooling medium is water, and the tempered troostite can be obtained after tempering.

Example 1

Smelting the elastic steel according to the elastic steel component requirement, and testing to obtain molten iron with the sulfur content of 0.0016% after the molten iron is pretreated by KR molten iron; then smelting in a converter, namely smelting in a BOF converter, and removing C by top-blown oxygen; CAS external refining, argon blowing, and removing impurities through a shielding case; forging the steel ingot into fillet square steel with the thickness of 115 mm multiplied by 380mm, and machining the square steel to ensure that the surface roughness of the square steel is 3.2; oil cooling and quenching for 60min, wherein the heating temperature is 890 ℃; water cooling and tempering for 90min, and heating temperature is 350 ℃.

The structure obtained by detection is a tempered troostite, and the steel ingot comprises the following components: c: 0.37 percent; si: 0.92 percent; mn: 1.15 percent; b: 0.01 percent; v: 0.04 percent; cr: 1.4 percent.

Processing the material into a test piece, and testing to obtain the material with the mechanical properties as follows:

TABLE 1

Tensile strength/MPa	Yield strength/MPa	Elongation percentage	Shrinkage rate
				1786	1568	10％	39％

Example 2

KR molten iron pretreatment is carried out, and the sulfur content of the molten iron obtained by testing is 0.0013%; smelting in a converter by adopting a BOF method, and removing C by top-blown oxygen; CAS external refining, argon blowing, and removing impurities through a shielding case; forging the steel ingot into two round steel with the diameter of 110 multiplied by 600mm according to the size of the processed warhead, and machining to ensure that the surface roughness of the round steel is 3.2; obtaining two elastomer blanks after hot stamping and rough machining; oil cooling and quenching for 60min, and heating at 900 ℃; water-cooling and tempering for 90min, and heating at 400 ℃; and finally obtaining two typical attack and hardness projectile bodies with certain calibers after finish machining, wherein one body is used for testing the tissue form, the components and the mechanical property of the material, and the other body is internally filled with TNT explosive and used for testing the dense killing radius.

The detected tissue form of the elastomer material is tempered troostite, and the components are as follows: c: 0.32 percent; si: 0.87 percent; mn: 1.10 percent; b: 0.01 percent; v: 0.05 percent; cr: 1.2 percent. The mechanical properties of the elastomeric material obtained by the test are as follows:

TABLE 2

Tensile strength/MPa	Yield strength/MPa	Elongation percentage	Shrinkage rate
				1762	1533	12％	47％

The experimental test shows that the dense killing radius of a typical attack-hardness bullet with a certain caliber manufactured by the materials and the process shown in the example is 28 m. According to the published literature, the elastic body material with the caliber of typical tapping and hardening bullet is D6AC, the yield strength is 1527MPa, the tensile strength is 1730MPa, and the elongation is 10%. The caliber typical tapping-hardness-bullet comparison standard bullet manufactured by the composition and the process shown in the application example 2 ensures the strength and the plasticity of the material and realizes the dense killing radius of 28m (basically reaching the level of a generation of explosive killing bullet).

As can be seen from tables 1 and 2, the elastic steel obtained by the components and the preparation method provided by the invention simultaneously meets the requirements of the clothing strength being more than or equal to 1500MPa and the elongation being more than or equal to 10%.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The bullet steel for penetrating and killing a multifunctional warhead is characterized by comprising the following chemical components in percentage by weight: c: 0.32-0.38%; si: 0.80-1.10%; mn: 0.95-1.25%; b: 0.010-0.015 percent; v: 0.04-0.06%; cr: 1.1-1.4%; the balance of Fe and inevitable impurities;

the preparation method of the elastic steel comprises the following steps:

pre-desulfurizing molten iron, smelting in a converter, deoxidizing and alloying, refining outside a CAS stirring furnace, secondary refining, forging, rough machining, hot stamping, quenching, tempering and finish machining;

the heat preservation time for quenching is 50min-70min, the heating temperature is 880-900 ℃, and the cooling medium is oil; the tempering is carried out for 80-100 min at 350-400 deg.C with water as cooling medium.

2. The bullet steel for penetration and killing of multifunctional warheads according to claim 1, wherein the molten iron pre-desulfurization is pre-treated with KR molten iron, and the content of sulfur is reduced to less than 0.002%.

3. The bullet steel for penetration and killing of multifunctional warheads according to claim 1, wherein the converter smelting adopts a BOF converter smelting and top oxygen decarburization (C).

4. The bullet steel for penetration and killing of multifunctional warheads according to claim 1, wherein said rough machining processes a steel ingot into a square steel with rounded corners having a certain size and a surface roughness of the square steel is not less than 3.2.