ON THE ORDERING TRANSFORMATIONS IN Ti_3AL-Nb ALLOY

Study was made of the behaviour of ordering transformation in Ti_3AI-Nb alloy,including theordering at high temperatures,the transformation of high temperature β-phase duringcooling,and the decomposition of metastable β-phase during aging.The results show that theordered primary α_2 and high temperature β in alloy form at 1060℃.The transformation ofhigh temperature β-phase proceed by β→α_2+ω type during cooling,and the decomposition ofmetastable β and ω type proceeded by(β+ω)_(metustabte)→(α_2+β)_(stable)during aging at 700℃.