Influence of precipitates and dislocations on the acoustic nonlinearity

摘要：

The influence of precipitates and dislocations on the acoustic nonlinearity was investigated in isothermally aged ferritic CrMo steel and low cycle fatigued copper. The variation in the normalized acoustic nonlinearity parameter (β/β0) was interpreted as resulting from microstructural changes supported by the electron microscopy. The β/β0 of CrMo steel increased abruptly in the initial stage of degradation, and then changed little due to the coarsening of carbide and precipitation of stable M6C carbide during isothermal aging. Due to the evolution of dislocation cell substructure, the β/β0 of copper increased with the fatigue cycles. These experimental results are illustrated that the acoustic nonlinearity is severely affected by the lattice strain caused by precipitates and dislocations.

关键词： Acoustic nonlinearity Precipitates Dislocations Isothermal degradation Fatigue

作者: Chung Soek KIM Tae Sung PARK Ik Keun PARK

作者单位: Dept. of Mechanical Engineering, Seoul National University of Technology,Seoul 139-743, Korea2 Gradu Graduate school of Energy and Environment, Seoul National University of Technology,Seoul 139-743, Ko

会议类型: 国际会议

会议名称: 第十七届世界无损检测会议(17th World Conference on Nondestructive Testing)

会议地点: 上海

会议语种:英文

页码: 1044-1049

在线出版日期: 2008-10-25（万方平台首次上网日期，不代表论文的发表时间）