The method of improving the plasticity of powder metallurgy high tantalum-tungsten alloys is to treat the high tantalum-tungsten alloy products after hot isostatic pressing in the preparation process of powder metallurgy high tantalum-tungsten alloy by adopting the process of sponge zirconium adsorption at high temperature and high temperature vacuum heat treatment. The invention adopts a two-step heat treatment method. Firstly, sponge zirconium deoxidizer is adopted to adsorb oxygen in high tantalum-tungsten alloy products, and then high temperature vacuum heat treatment is adopted to promote the volatilization of oxygen and oxide in high tantalum-tungsten alloy products, promote the diffusion and escape of solid dissolved oxygen in the grain boundary, effectively reduce the oxygen content, purify the grain boundary, and improve the binding force of the grain boundary. And release the internal stress generated by hot isostatic pressing, while ensuring the strength of high tantalum-tungsten alloy, greatly improve the plasticity of the alloy.
Tantalum-tungsten alloy is a very important and widely used tantalum alloy in high temperature resistance, impact and dynamic mechanical properties of excellent materials, especially high tantalum-tungsten alloy, mostly used in some extremely harsh conditions of the working environment. High tungsten tantalum alloy has higher creep strength and low creep rate, so these tantalum-tungsten alloy is a better candidate material for heat-resistant erosion components, because of its high density, high melting point, good corrosion resistance, good workability, weldability and other characteristics, in recent years has been gradually used in weapons, aerospace and other fields. At present, the main high tantalum-tungsten alloy used in China are Ta10W and Ta12W. As refractory metal alloys, tantalum-tungsten series alloys have the characteristics of easy oxidation at high temperatures, and are generally prepared by vacuum electron beam melting. Tantalum-tungsten alloy ingots with electron beam melting have low impurity and gap element content, uniform composition, good plasticity, oxygen content can be easily controlled below 0.01%; The elongation of Ta10W and Ta12W alloys using electron beam melting can reach 20% ~ 40% after pressure processing.
High tantalum-tungsten alloy due to high strength, easy oxidation, so that the pressure processing and molding becomes difficult, although the current conventional plate and bar production process has been more mature, but by the electron beam melting cast ingot size limitations, some large size alloy components, shaped parts, thin (thick) wall cylindrical parts, such as electron beam melting combined with pressure processing is difficult to achieve, therefore, Such products and components can only be prepared by powder metallurgy.
