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采用标准试样，测试了全层片组织Ｔｉ３３Ａｌ３Ｃｒ０．５Ｍｏ（质量分数，％，下同）合金的室温断裂韧性（以下简称断裂韧性）。在ＳＥＭ、ＴＥＭ下原位观察了板状和薄膜状合金试样中裂纹产生及扩展的动态过程。发现试样的断裂韧性因层片板条取向的不同而呈现各向异性，α２相层片板条对裂纹的扩展具有阻碍作用并使裂尖发生钝化。基于以上原因，使得层片板条取向呈现随机性的合金试样具有高的室温断裂韧性。
The standard samples were used to test the room temperature fracture toughness (hereinafter referred to as fracture toughness) of the full-thickness Ti-33Al 3 Cr 0.5 Mo (mass fraction, same below) alloy. The dynamic process of crack initiation and propagation in plate-like and film-like alloy specimens was observed in situ under SEM and TEM. It is found that the fracture toughness of the specimen shows anisotropy due to the orientation of the lamellar lamellae. The α2 phase lamella lays a hindrance to the crack growth and passivates the crack tip. Based on the above reasons, alloy specimens with stratum lamella orientation randomness have high room temperature fracture toughness.