A method for manufacturing a variable cross-section rotary body shaped charge
By combining two-stage heating forging with closed-die forging technology, the problems of low production efficiency and material utilization of propellant liner were solved, achieving efficient production of high-precision propellant liner and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA WEAPON SCI ACADEMY NINGBO BRANCH
- Filing Date
- 2025-01-15
- Publication Date
- 2026-07-24
AI Technical Summary
Existing technologies for preparing propellant liner have problems of low production efficiency and low material utilization, especially for high-melting-point, high-strength, and high-hardness alloy materials such as zirconium alloys, titanium alloys, and tantalum alloys, which are difficult to form and efficiently shape with fine equiaxed grains using existing processes.
The two-stage heating forging method, including primary forging and secondary forging, combined with closed-die forging technology, forms the approximate shape of the target part through primary forging and then shapes it through secondary forging. Combined with glass antioxidant spraying and finishing, it improves material utilization and production efficiency.
It achieves high material utilization (≥75%) and high production efficiency for the shaped charge, reduces manufacturing costs, and improves the precision and forming quality of the parts.
Smart Images
Figure CN119794740B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of drug liner preparation technology, and specifically to a method for preparing a variable cross-section rotating drug liner. Background Technology
[0002] For munitions used in aviation, weaponry, and naval applications, the shaped charge liner is often referred to as the heart of the projectile. It is a simple rotating component, including hemispherical, spherical-conical, and flared shapes. Common manufacturing methods include free forging and machining, spinning, and casting. Due to the large demand for shaped charge liners, cost control necessitates the development of new manufacturing methods or improvements to existing processes.
[0003] For materials used in propellant liner manufacturing (such as zirconium alloys, titanium alloys, copper alloys, and tantalum alloys), optimizing manufacturing processes to improve material utilization is paramount. For example, titanium and tantalum alloys are relatively expensive, making improved material utilization an effective way to save costs. Propellant alloys are high-melting-point, high-strength, and high-hardness materials that are difficult to deform. While pressure processing methods such as spinning and rolling can achieve near-net-shape forming, these methods result in relatively small material deformation, making it difficult to form fine equiaxed grains.
[0004] Traditional pressure processing techniques such as die forging and extrusion are used to manufacture shaped charge covers. However, due to significant differences in deformation between different parts—large deformation at the opening and small deformation at the core—the inconsistent deformation results in uneven grains after annealing. For example, patent number CN11558448B describes a method for step-forming tantalum alloy shaped charge covers under temperature and cold loads. Using multiple passes (5-10 times) of forward and reverse extrusion and straightening processes, low-texture-strength tantalum alloy shaped charge covers can be produced, significantly reducing processing costs. However, under the condition of a high number of passes and small deformation, high requirements are placed on equipment control precision and die life, and production efficiency is also greatly reduced. Furthermore, conventional methods for preparing shaped charge covers involve: extruding bar stock, free forging, and stamping + machining to prepare rotating shaped charge cover blanks. These methods result in large machining allowances and low material utilization. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a method for preparing a variable cross-section rotating propellant liner that combines production efficiency and material utilization, in light of the above-mentioned technical status.
[0006] 1. The technical solution adopted by the present invention to solve the above-mentioned technical problem is: a method for preparing a variable cross-section rotating propellant liner, characterized by comprising the following steps:
[0007] S1 First heating: Heating the blank and preheating the mold;
[0008] S2 single-stage forging: The heated billet is removed from the heat treatment furnace and placed into the lower die for positioning. The forging speed is 0.1-5 seconds. -1 Forging impact force 700-850T;
[0009] S3 Secondary Heating: After the billet after S2 die forging is removed and cooled to room temperature, it is heated again;
[0010] S4 Secondary Die Forging: The heat-treated alloy is then placed into the die, positioned, and deformed at a forging rate of 0.01-5s. -1 The impact force of die forging is 300-500T;
[0011] S5 Annealing: After the billet obtained in S4 is taken out, it is subjected to recrystallization annealing and then cooled to room temperature;
[0012] S6 post-processing: The blank after S5 annealing is finely processed to obtain a rotating shaped charge shroud.
[0013] To reduce high-temperature oxidation, preferably, a glass antioxidant is sprayed onto the blank before heating in step S1.
[0014] Preferably, material preparation is required before heating in step S1. The material preparation step is as follows: based on the structural dimensions, volume, and weight of the shaped charge, alloy discs of appropriate thickness are cut from the alloy rod using wire cutting as blanks. Using alloy discs as blanks makes them easier to place into the mold cavity, reducing the weight of the prepared material and thus increasing material utilization.
[0015] Preferably, the heating temperature in step S1 is higher than the recrystallization temperature of the billet, and the holding time is 1-3 hours; the preheating temperature of the mold is 200-300℃. Preheating the mold can prevent excessive temperature drop of the billet during forging. The longer holding time ensures that the structure of the billet reaches equilibrium under this temperature condition.
[0016] Preferably, the heating temperature in step S3 is higher than the recrystallization temperature of the billet, and the holding time is 0.5-1.5 hours. Compared with step S1, the shorter holding time avoids changes in the microstructure; prolonged holding after the billet reaches the desired temperature may damage the microstructure after forging.
[0017] Preferably, the cooling in step S5 is furnace-in-furnace cooling, and the cooling and heat preservation time is 1-5 hours.
[0018] Preferably, the material utilization rate of this preparation method is ≥75%.
[0019] Preferably, the primary and secondary forgings are closed-die forgings. Closed-die forging, also known as flash-free forging, maintains a constant gap between the upper and lower dies during the forging process. The billet is formed within a closed die cavity, preventing the generation of transverse flash and increasing material utilization. Furthermore, a small amount of excess material may form longitudinal burrs, which are easily removed during post-processing. Employing isothermal closed-die forging technology for precision forging can significantly improve material utilization and forging efficiency, thereby reducing costs.
[0020] Compared with the prior art, the advantages of the present invention are as follows: two-stage heating forging is performed, with one forging to fill the mold and obtain the approximate shape of the target part; after the first forging, the edge of the part rebounds, so a second forging is performed to shape it. The production efficiency is high with only two forging stages; moreover, the impact force of the first forging is large, reaching 700-850T, thereby obtaining the approximate shape of the target part. Due to the large impact force, the springback of the blank after forging is also large, while the impact force of the second forging is smaller, resulting in less springback of the blank after the second forging, which can maintain the required shape and achieve high precision, reduce the allowance in the manufacturing process, and increase the material utilization rate. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of closed-die forging in Example 1;
[0022] Figure 2 This is a schematic diagram of the rotating propellant liner prepared in Example 1;
[0023] Figure 3 This is a schematic diagram of the rotating propellant shroud prepared in Example 2.
[0024] In the diagram: 1. Upper mold; 2. Lower mold; 3. Mold core; 4. Rotating shaped charge cover. Detailed Implementation
[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0026] Example 1
[0027] like Figure 1-2 The image shows a preferred embodiment of the present invention. The method for preparing the zirconium alloy variable cross-section rotating propellant liner specifically includes the following steps:
[0028] S1 Material Preparation: Prepare zirconium alloy rods. Based on the structural dimensions, volume, and weight of the rotating propellant liner, cut zirconium alloy discs of appropriate thickness (145mm*10mm) as blanks using wire cutting. After weighing, spray the blanks with anti-oxidation coating KBC-12.
[0029] S2 First heating: The blank is placed in a heat treatment furnace and heated to 980℃ for 1 hour; the mold is preheated to 200-300℃.
[0030] S3 single-stage forging: The billet heated by S2 is taken out of the heat treatment furnace and placed into the lower die for positioning. The forging speed is 0.1-5s. -1 The forging impact force is 700-850T, which completely fills the cavity with the billet.
[0031] S4 Secondary Heating: After the billet after S3 die forging is removed and cooled to room temperature, it is reheated in the furnace; the heating temperature is 980℃ and the holding time is 0.5 hours.
[0032] S5 secondary die forging: The heat-treated alloy is then placed into the die, positioned, and deformed at a forging rate of 0.01-5s. -1 The forging impact force is 500T;
[0033] S6 Annealing: After the billet obtained from S5 is taken out, recrystallization annealing is carried out at 1150℃ for 5 hours, and then cooled to room temperature in the furnace.
[0034] S7 Post-processing: The annealed billet is then precision-machined on a lathe to obtain the following: Figure 2 The rotating propellant liner shown. After weighing, the material utilization rate of the preparation method in this embodiment was determined to be no less than 75%.
[0035] Example 2
[0036] The preparation method of the variable cross-section rotating propellant liner specifically includes the following steps:
[0037] S1 Material Preparation: Prepare TC4 titanium alloy bars. Based on the structural dimensions, volume, and weight of the rotating shaped charge liner, cut 105mm*5mm round pieces of the appropriate thickness using wire cutting as blanks. Treat the upper and lower end faces and outer diameter by cutting or grinding to obtain a metallic luster. After weighing, spray the blanks with anti-oxidation coating KBC-12 to reduce high-temperature oxidation.
[0038] S2 First heating: The blank is placed in a heat treatment furnace and heated to 920-980°C at a heating rate of 5-8°C / min, and held for 0.5-1.5 hours; the mold is preheated to 200-300°C.
[0039] S3 One-time Forging: The billet heated by S2 is taken out of the heat treatment furnace and placed into the lower die for positioning. The forging speed is 5 seconds. -1 The forging impact force is 800T, which completely fills the cavity with the billet.
[0040] S4 Secondary Heating: After the S3 die-forged billet is removed and air-cooled to room temperature, it is reheated in the furnace; the heating temperature is 920~980℃, and the holding time is 0.5~1.5 hours.
[0041] S5 secondary die forging: The heat-treated alloy is then placed into the die, positioned, and deformed at a forging rate of 0.01-5s. -1 The forging impact force is 500T;
[0042] S6 Annealing: After the billet obtained from S5 is taken out, recrystallization annealing is carried out at a temperature of 850℃ for 2 hours, and then cooled to room temperature in the furnace.
[0043] S7 Post-processing: The annealed billet is then precision-machined on a lathe to obtain the following: Figure 3 The rotating propellant liner shown. After weighing, the material utilization rate of the preparation method in this embodiment was determined to be no less than 75%.
Claims
1. A method for preparing a variable cross-section rotating propellant liner, characterized in that: Includes the following steps: S1 First heating: The blank is heated and the mold is preheated; the heating temperature in step S1 is higher than the recrystallization temperature of the blank, and the holding time is 1-3 hours; the preheating temperature of the mold is 200~300℃. S2 single-stage forging: The heated billet is removed from the heat treatment furnace and placed into the lower die for positioning. The forging speed is 0.1-5 seconds. -1 Forging impact force 700-850T; S3 Secondary Heating: After the billet forged in S2 is removed and cooled to room temperature, it is heated again; the heating temperature in step S3 is higher than the recrystallization temperature of the billet, and the holding time is 0.5-1.5 hours. S4 Secondary Die Forging: The heat-treated alloy is then placed into the die, positioned, and deformed at a forging rate of 0.01-5s. -1 The impact force of die forging is 300-500T; S5 Annealing: After the billet obtained in S4 is taken out, it is subjected to recrystallization annealing and then cooled to room temperature; S6 post-processing: The blank after S5 annealing is finely processed to obtain a rotating shaped charge shroud.
2. The method for preparing a variable cross-section rotating propellant liner according to claim 1, characterized in that: Before heating in step S1, a glass antioxidant is sprayed onto the blank.
3. The method for preparing a variable cross-section rotating propellant liner according to claim 1, characterized in that: Before heating in step S1, material preparation is required. The material preparation steps are as follows: according to the structural dimensions, volume and weight of the shaped charge, alloy discs of corresponding thickness are cut from the alloy rod using wire cutting as blanks.
4. The method for preparing a variable cross-section rotating propellant liner according to claim 1, characterized in that: The cooling in step S5 is furnace-side cooling, and the holding time for cooling is 1-5 hours.
5. The method for preparing a variable cross-section rotating propellant liner according to any one of claims 1-4, characterized in that: The material utilization rate of the aforementioned preparation method is ≥75%.
6. The method for preparing a variable cross-section rotating propellant liner according to any one of claims 1-4, characterized in that: The primary and secondary forgings are closed-die forgings.