Tantalum-2.5Tungsten, with its excellent corrosion resistance, largely inherits the corrosion resistance advantages of tantalum, and even surpasses it in some scenarios. It can resist the erosion of highly corrosive media such as boiling concentrated hydrochloric acid, 98% concentrated sulfuric acid, and aqua regia, but it is not resistant to hydrofluoric acid. This characteristic makes it more reliable than metals such as titanium and zirconium in highly corrosive chemical environments. It has a high melting point of around 3005℃ and can withstand temperatures above 2500℃ for short periods. At high temperatures, a dense Ta₂O₅ oxide film forms on the surface, allowing it to operate for extended periods in high-temperature environments under inert gas protection, making it suitable for high-temperature reactions and heat exchange applications.
Ta-2.5W alloy has a single-phase solid solution structure, retaining the easy-to-process characteristics of tantalum. It can be manufactured into various forms such as wires, tubes, and plates through cold and hot working processes. For example, it can be processed into tubes with outer diameters of 1.5-170mm and wall thicknesses of 0.2-5.0mm. Its weldability is similar to pure tantalum, with a stress-relief temperature of 1000℃ and a recrystallization temperature of 1200-1300℃. By controlling the processing and heat treatment, the grain size can be flexibly adjusted to meet the material performance requirements of different scenarios. The tantalum-2.5 tungsten alloy is primarily composed of approximately 97.5% tantalum, with tungsten content controlled at 2-3.5%. Simultaneously, the total content of impurities such as carbon, oxygen, nitrogen, and iron is strictly limited to ≤0.1%, and the niobium content is specified to not exceed 0.5%. This strict composition control avoids grain boundary embrittlement, ensuring the overall stability of the alloy's performance and conforming to industry standards such as GB/T 14841 or ASTM B365.
Tantalum-2.5 tungsten is used to manufacture heaters, heat exchangers, reactor linings, and spiral tubes for handling highly corrosive media, especially under high-temperature conditions with slight reducing properties or hydrogen content risks, where its performance surpasses that of pure tantalum. It is also used to manufacture rocket nozzles, jet engine components, high-temperature heat exchangers, and other components that need to withstand extremely high temperatures and stresses. Tantalum-2.5Tungsten is used in the manufacture of implants and surgical instruments, but its applications are not as widespread as pure tantalum and Ti-6Al-4V. It is typically used when specific strength requirements are present. In wafer manufacturing, it is used for components requiring high purity and corrosion resistance, such as scaffolds and fixtures.
Tantalum-2.5Tungsten is a solid solution-strengthened refractory alloy with excellent overall performance. Its core advantage lies in significantly improving the material's high-temperature strength and resistance to hydrogen embrittlement without sacrificing tantalum's excellent corrosion resistance and processing plasticity. This makes it an ideal alternative to pure tantalum and high-tungsten tantalum alloys in extreme corrosion, high-temperature, and special environments. It strikes a good balance between plasticity and strength: unlike high-iron alloys such as tantalum-10Tungsten, which suffer from a significant decrease in ductility due to high tungsten content, tantalum-2.5Tungsten exhibits an elongation of ≥20% in the annealed state and maintains over 8% in the cold-drawn state. It can withstand bending, stretching, and other forming operations while meeting the strength requirements of most scenarios, avoiding the contradiction of "high strength but difficult forming."
