The forming method of tantalum alloy special-shaped parts includes the following steps: Step 1. Hot stamping is carried out after the surface of the tantalum alloy round plate is polished to obtain semi-finished tantalum alloy special-shaped parts; Step 2. The semi-finished tantalum alloy special-shaped parts are cold spinning or hot spinning to get the blank of tantalum alloy special-shaped parts; Step 3. The blank of special-shaped tantalum alloy is cut and machined successively, and then vacuum annealed to obtain special-shaped tantalum alloy. This invention first hot stamping method is used to make the preliminary forming tantalum alloy plate, tantalum alloy profiled semi-finished products, and then the spinning method is adopted to make the inner surface of the tantalum alloy profiled semi-finished products and spinning mould fully fit, so as to ensure inner surface and outer surface thinning even spin, solved the tantalum alloy thick plate in the process of preparation of tantalum alloy profiled stamping difficulty and the problem of difficult to control in spinning size, The finished rate and surface quality of tantalum alloy special-shaped parts are improved.
Tantalum and its alloys have high density, high melting point, high strength and excellent acid and alkali resistance and liquid metal corrosion resistance, which are widely used in chemical, aerospace, weapons and equipment, electronics and other fields. To prevent corrosion, tantalum and tantalum alloy are used as the lining of heat exchangers, shells, tubular heaters and thermocouple bushing in chemical equipment, as well as the sealing heads of acid-making vessels, pipes, storage tanks and transport tanks. In the aerospace field, tantalum alloy is used as rocket nozzle material. In the field of weapons and equipment, tantalum alloy, as the material of armour-breaking ammunition cover, greatly improves the penetrating power of the penetrating body. In recent years, with the development of the above fields, the demand for tantalum and its alloys has increased sharply.
Most tantalum alloy products are shaped like tubular, hemispherical and spherical shaped rotary parts. In order to ensure the performance of the products, the shaped rotary parts cannot be welded. Most of them are made by stamping or spinning tantalum alloy sheet. Studies have shown that the internal structure of tantalum alloy plate inevitably has anisotropy, so it is easy to produce lug in the stamping process, resulting in the decline of product yield, as shown in FIG. 1. When the tantalum alloy sheet is thick, the ear making phenomenon is serious in the stamping process, the product is difficult to form, and the scrap rate is high, resulting in a great waste of materials, especially for tantalum, an expensive metal, which greatly increases the raw material cost. And spinning method using tantalum alloy thick plate preparation of tantalum alloy profiled, wheel pressure is difficult to accurately passed to the inner surface of the spinning pieces, causing the outer surface of the spinning pieces have been thinned and still stick on the inner surface mould problem, make the products size is difficult to control, especially in processing complicated shape and the depth of the larger products, direct spinning susceptible to cracking phenomenon. Therefore, the yield of special tantalum alloy by stamping or spinning thick tantalum alloy plate is low.
