NONDESTRUCTIVE EVALUATION OF RESIDUAL STRESS AND TGO BY USING LASER ULTRASONIC METHOD

摘要：

Noncontact laser ultrasonic methods are provided for nondestructive characterization of surface residual stress and thermally growth oxide (TGO) in thermal barrier coating (TBC).Stress-acoustic coefficients of Rayleigh wave were used to characterize the surface residual stresses of TBC specimens which were prepared by electronic beam physical vapor deposition (EB-PVD) method.The ultrasonic testing results of TBC specimens before and after oxidation with 1 time and50 times agree well with the corresponding Raman spectral analyses.Meanwhile,a physical mode of thin multi-layered structure is established for the case of received ultrasonic longitudinal waveform consisting of reverberant overlapping echoes.Further,the transform function of the mode was derived to evaluate the TGO in this work.The experimental transform functions of TBC specimens above shows that the amplitude decreases at high order resonant frequencies with increase of TGO thickness.The proposed methods are able to nondestructively characterize the local surface stress and TGO in TBC,and are important to practical engineering application.

关键词： Laser ultrasonic Thermal barrier coating Residual stress Thermally growth oxide Transfer function

作者: Yang ZHAO Jian-wei CHEN Zhen-zhen ZHANG Yin-nian ZHU

作者单位: Laser Institute of Shandong Academy of Science, 28789 Jingshi east Road, Jinan, 250103, P.R.China;Ce Laser Institute of Shandong Academy of Science, 28789 Jingshi east Road, Jinan, 250103, P.R.China Center for Quality Engineering and Failure Prevention, Northwestern University, Evanston, IL 60208,

会议类型: 国际会议

会议名称: The 2015 Symposium on Piezoelectricity,Acoustic Waves and Device Applications(2015全国压电和声波理论及器件技术研讨会)

会议地点: 济南

会议语种:英文

页码: 411-417

在线出版日期: 2015-10-30（万方平台首次上网日期，不代表论文的发表时间）