Internal defect detection using lock-in thermography

• Main Authors: Tsan-nien Chen, 陳贊年
• Other Authors: Te-yuan Chung
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/45457800827895975325

碩士 === 國立中央大學 === 光電科學與工程學系 === 101 === This research successfully builds a non-destructive, non-contact detection method of determining the internal defect depth and defect radius in samples. In lock-in thermography method, the samples are measured by periodically changed heat flux. The effect about periodically changed heat flux is known as thermal wave effect. As thermal wave effect shows, the detection depth is related with the frequency of heat flux By finite element analysis software, the defect depth and defect radius we can be measured after using two difference frequency heat power detect a sample. The simulation results are proved by experiment.