According to the content of different industrial impurities in titanium, divided into TA1, TA2 and TA3 three grades. The three kinds of industrial pure titanium gap impurities are gradually increased, so its mechanical strength and hardness also increases step by step, but a corresponding decline in ductility, toughness.
Industrial pure titanium commonly used in industry is TA2, due to its corrosion resistance and moderate mechanical properties. TA3 can be used when the requirements of wearability and strength are high. TA1 is available for better forming properties.
TA1, TA2 and TA3 in the national standard correspond to Gr0, Gr1 and Gr2 in this UNS.
TA1, TA2 have good low temperature toughness and high low temperature strength with iron content of 0.095%, oxygen content of 0.08%, hydrogen content of 0.009% and nitrogen content of 0.0062% -253 ℃ below the low temperature structural materials.
TA2 contains titanium (Ti) balance, iron (Fe) ≤0.30, carbon (C) ≤0.10, nitrogen (N) ≤0.05, hydrogen (H) ≤0.015, oxygen (O) ≤0.25.