Control of microstructure and properties for tantalum-tungsten alloy component manufacturing in cold forging and subsequent annealing process

In mechanical engineering and intelligent manufacturing research area, excellent surface quality and dimensional accuracy at the macro level for products manufactured by means of information and intelligent technology are desired, at the same time, their controls of microstructure and properties at the microscopic scale are also of great concern. Tantalum-tungsten (Ta-W) alloy components are widely used in high temperatures, ballistics, and aerospace fields due to their advantages of high density, high plasticity, and good corrosion resistance. Therefore, in this paper, by studying the influence of processing parameters of heat treatment on microstructure and properties in cold forging deformation, tantalum-tungsten alloy components with homogeneous and fine-grained microstructure as well as excellent mechanical properties can be successfully achieved. Results show that the average grain size of Ta-W alloy components reaches the minimum when annealed at 1300 °C for 60 min, which is less than 25 μm. The recrystallization process of Ta-W alloy components with a reduction of 74% has completed at the annealing temperature of 1300 °C, and apparently grain growth occurs when the annealing temperature reaches 1400 °C. With the increase of annealing temperature paremeters, the microhardness of Ta-W alloy components decreases at first then slightly increases. The increase of microhardness at 1400 °C is likely due to the tendency of refractory metals to oxidize at high temperatures. After annealing treatment, the deformation of Ta-W alloy components shows obvious elastic-plastic deformation behavior, and its elongation reaches a maximum value of 46%.