Tantalum alloy has the advantages of high density, high temperature resistance, high strength, good machining performance, fracture toughness, corrosion resistance, etc. It is an indispensable important material in aviation, aerospace, chemical industry, nuclear industry, high temperature technology and other fields, and has a good application prospect. Tantalum tungsten alloy is mostly used in ultra-high temperature, ultra-high pressure, high-speed airflow erosion, rapid cooling and rapid heating and other extreme environment of ultra-high temperature structural components, such as rocket engine high-temperature structural materials, heat-resistant skin of hypersonic reentry vehicle, thermal protection of space shuttle, nuclear fuel cladding materials, etc. Ablative rudder blades, combustion chambers for supersonic aircraft, control parts and regulating devices for rockets, missiles and jet engines.
However, when the temperature exceeds 1200℃, the high temperature strength of tantalum tungsten alloy decreases significantly. Tantalum alloy with high alloy concentration can be formed by adding alloying elements to tantalum, and its high temperature mechanical properties are significantly improved and its processing properties are good. Therefore, it is used as a high temperature structural material. However, the prospect of its application in ultra-high temperature and harsh environment is limited due to the substantial improvement of its mechanical properties. At the same time, the preparation method of tantalum tungsten alloy is generally the use of electron bombardment melting method, and the tantalum alloy cast ingot obtained by electron bombardment melting method has a coarse grain, reaching an average of 3-5mm, which is unfavorable to the mechanical properties of the material. In addition, tantalum tungsten alloy is easy to absorb oxygen and oxidize when exposed to air above 300 ° C, which also limits the application of tantalum tungsten alloy. Therefore, it is necessary to overcome the shortcomings of single-phase tantalum tungsten alloy through the second phase dispersion strengthening. The ceramic phase is designed to add ceramic phase to the tantalum tungsten alloy, and through alloying and process control, the tiny particles of ceramic phase are evenly dispersed on the tantalum matrix, so that its mechanical properties at room temperature, high temperature mechanical properties and high temperature oxidation resistance can be significantly improved. Based on this, it is particularly necessary to design a Ta-W-Al-Al2O3 alloy bar and its preparation method.
Aiming at the shortcomings of the prior art, the invention aims to provide a Ta-W-Al-Al2O3 alloy bar and a preparation method. The Ta-W-Al-Al2O3 alloy bar prepared by the method has good plasticity and tensile strength at room temperature, excellent high temperature tensile strength and oxidation resistance, and can be used in the air environment of 1500℃.
