High strength and high toughness beta titanium alloy

Beta titanium alloys were originally developed in the mid-1950s as B120VCA alloys (Ti-13v-11Cr-3Al). β type titanium alloy has good cold and hot processing properties, easy forging, rolling, welding, can be obtained by solution - aging treatment of high mechanical properties, good environmental resistance and strength and fracture toughness of good coordination. The new high-strength and high-toughness β-type titanium alloys are representative of the following: Ti1023 (Ti-10v-2Fe-#al), which is equivalent to the 30CrMnSiA high-strength structural steel commonly used in aircraft structural parts, and has excellent forging performance; Ti153 (Ti-15V-3Cr-3Al-3Sn), the cold working performance of the alloy is better than that of industrial pure titanium, and the tensile strength at room temperature after aging can reach more than 1000MPa; β21S (Ti-15Mo-3Al-2.7Nb-0.2Si) is a new type of anti-oxidation and ultra-high strength titanium alloy developed. It has good anti-oxidation properties and excellent cold and hot processing properties. It can be made into 0.064mm thick foil. Japan Steel Pipe Company (NKK) successfully developed SP-700 (Ti-4.5Al-3V-2Mo-2Fe) titanium alloy, the alloy has high strength, superplastic elongation up to 2000%, and the superplastic forming temperature is 140℃ lower than Ti-6Al-4V. It can replace Ti-6Al-4V alloy to manufacture various aerospace components with superplastic-diffusion connection (SPF/DB) technology; The BT-22 (Ti-5V-5Mo-1Cr-5Al) developed by Russia has a tensile strength of more than 1105MPa.