Titanium alloy can be divided into three categories according to the phase composition: α alloy, (α + β) alloy and β alloy, China, respectively, TA, TC, TB said.
① α alloy contains a certain amount of stable α-phase elements, the equilibrium state is mainly composed of α-phase. α alloy small proportion, good thermal strength, good weldability and excellent corrosion resistance, the disadvantage is low strength at room temperature, usually used as heat-resistant materials and corrosion-resistant materials. Alpha alloys are generally subdivided into all-alpha alloys (TA7), near-alpha alloys (Ti-8Al-1Mo-1V) and alpha alloys (Ti-2.5Cu) with small amounts of compounds.
② (α + β) alloy contains a certain amount of stable α and β phase elements, the equilibrium state of the alloy phase α and β phase. (α + β) alloy with moderate strength and heat treatment can be strengthened, but the welding performance is poor. (α + β) alloy is widely used, of which the production of Ti-6Al-4V alloy accounts for more than half of all titanium.
Titanium rodsTitanium stick (3 photos)
③ β alloy contains a large number of stable β-phase elements, high-temperature β-phase can be all retained to room temperature. Beta alloys are usually subdivided into heat-treatable beta alloys (metastable beta and near-beta stable beta alloys) and thermostable beta alloys. The heat-treatable β-alloy has excellent plasticity in the quenched state and can achieve a tensile strength of 130 to 140 kgf / mm2 by aging treatment. Beta alloys are commonly used as high strength and tough materials. The disadvantage is the proportion of large, high cost, poor welding performance, cutting difficult.