钛合金中微裂纹的超声红外热像检测技术研究

Sonic infrared nondestructive evaluation of microcracks in titanium alloy

研究了超声红外热像检测技术的原理,利用有限元分析方法,建立了钛合金刀具样件和裂纹的二维热传导有限元模型,通过有限元数值计算方法,对超声波在裂纹处激发的热源引起的瞬态温度场进行分析,然后对含有微裂纹的钛合金刀具样件进行实际检测。结果表明,超声红外热像检测技术对钛合金材料中的微裂纹定性检测快速有效,且是无损检测。对微裂纹检测的实验结果与利用有限元方法计算结果基本一致,证明有限元模型的正确性,并为钛合金材料中微裂纹的定量检测提供了新的方法和参考依据。

Based on the mechanism of sonic IR imaging and finite-element computation, a finite element model（FEM） of 2D heat conduction was established and used to compute the temperature variety process on the surface of samples excited by ultrasound in the defects. An experiment setup was established to test of microcracks in the samples made of titanium alloy. The results show that sonic IR imaging technique is convenient and effective in qualitative detection of the microcracks in titanium alloy. Result of the computation results fit well with the experiment, which indicates that the FEM is correct. The significance of this study lies in the fact that it is methodologically innovative and empirically valuable for providing a reference for nondestructive evaluation of mi- crocracks in titanium alloy.