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TiAl广泛应用在在航空航天和汽车等领域,研究了硼对高铌TiAl基合金γ→α相变的影响。研究发现:在相同的保温时间下,Ti-46Al-8Nb-0.8B合金α2相的体积分数比Ti-46Al-8Nb合金小,这主要是因为Ti-46Al-8Nb-0.8B合金中的α相从γ晶界析出的形核率低,生长更困难而导致的;微量元素硼的添加能显著促进片状α相从γ晶粒内析出的形核率,抑制块状α相从γ晶界析出的形核率,并能阻碍α相的生长。
TiAl is widely used in aerospace and automotive fields to study the effect of boron on the γ → α transformation of high-niobium TiAl-based alloys. It is found that the volume fraction of α2 phase of Ti-46Al-8Nb-0.8B alloy is smaller than that of Ti-46Al-8Nb alloy at the same holding time, which is mainly due to the fact that the α phase in Ti-46Al-8Nb-0.8B alloy The nucleation rate of γ precipitated from γ grain boundary is low and the growth is more difficult. The addition of trace element boron can significantly promote the nucleation rate of α-phase precipitated from γ grains, Precipitation rate of nucleation, and can hinder the growth of α-phase.