Tantalum Tungsten alloy
Tantalum based alloy is formed by adding a certain amount of tantalum. The Ta-W binary alloy composed of Ta and W is an infinite solid solution. The strength of the alloy increases with the increase of tungsten content, but the plasticity of recrystallized alloy decreases significantly when the content of tungsten exceeds 12% ～ 14%. Ta-2.5W, ta-7.5w and Ta-10W are commercially produced. These tantalum alloys maintain the low-temperature plasticity of pure tantalum, and have high strength and oxidation resistance. Since the 1960s, tantalum tungsten alloys have been used in aerospace industry and chemical industry as high temperature structural materials and corrosion-resistant materials. In 1979, Ta-10W alloy developed in China was put into industrial production.Br>
The preparation method mainly adopts vacuum electron beam melting or vacuum arc melting for more than two times, then forging or extruding at temperature above 1200 ℃ and rolling and drawing below 500 ℃ to make plate, bar, wire, pipe and other products.
Cutting, welding, heat treatment and coating are the same as tantalum alloy.Br>
Application because the strength of tantalum tungsten alloy is higher than that of pure tantalum, and its corrosion resistance is similar to that of pure tantalum, so it has been widely used in chemical industry and aerospace industry. Ta-2.5W alloy is mainly used in heater, cooling coil, heat exchanger and reactor. Ta-7.5w alloy is mainly used as spring material and other corrosion resistant elastic elements in chemical corrosion equipment. Due to the high potential of tantalum and tantalum alloy, they become cathodes when they contact with other metals and absorb atomic hydrogen easily, which makes tantalum and tantalum alloy brittle. Therefore, when it is used to manufacture chemical equipment, it must be prevented from becoming cathode. Ta-10W alloy can be used as high temperature components such as thrust combustion chamber of liquid rocket engine with gas temperature above 3300 ℃ and heater of high temperature vacuum furnace.
