B元素对Ti-46Al和Ti-46Al-5Nb(原子分数,%)合金的柱状晶组织均有明显的细化作用,且对后者的细化效果更显著。这一现象可归结为:B元素在Ti-46Al-5Nb合金中的溶解度较低,硼化物析出量增加,柱状晶组织进一步细化。
B addition can refine the columnar structures of Ti-46Al and Ti 46Al-5Nb (atomic fraction, %) alloys, and the refining is obvious for the alloy Ti-Al Nb, which can be explained by the lower solubility of B in Ti-46Al-5Nb, resulting in more borides precipitated and inhabited grain growth.