TiAl基合金双态组织试样室温断裂的研究

来源期刊：中南大学学报(自然科学版)1997年第1期

论文作者：贺跃辉 黄伯云 曲选辉 刘文胜 陈小群

文章页码：43 - 46

关键词：TiAl基合金;双态组织;室温断裂韧性;裂纹

Key words：TiAl loased alloy;duplex microstructure;toughess at room temperature;crack fracture

摘    要：采用预制缺口试样，测试了Ti－33%Al－3%Cr－0.5%Mo(质量分数)合金双态组织材料的室温KIC值.使用扫描电子显微镜，研究了薄板状试样内裂纹扩展动态过程；并采用透射电子显微镜，进一步研究了薄膜试样内裂纹扩展动态过程，以及裂纹尖端附近区域上的变形亚结构.试验结果表明，TiAl基合金双态组织试样表现出低的室温断裂韧性，归因于γ相晶粒内容易形成剪切带，造成了γ相晶粒对裂纹扩展表现出低的阻力.

Abstract: The K_IC value of Ti-33%Al-3%Cr-0 5%Mo alloy sample with duplex microstructure at atmosphere temperature was measured. The crack growth process of thin plate sample at tensile stress was observated kineticly using SEM. And the crack expansion and the substructure around the crack tip were investigated on TEM. The test results show that the low fracture toughness of the sample with duplex microstructure is due to the formation easy of shearing tear crack at gamma grains, which expressed that the hinder force of gamma phase gains to the crack growth was small.