Automated Inspection of Laser Welded Blanks

Laser welded sheet metal blanks have been inspected for weld integrity using many different approaches. To date, visual inspection by human operators has been the most reliable method to detect weld defects. However, the ever increasing application of laser welded blanks in automotive body components has lead to larger blank sizes and volumes, resulting in the automation of the laser blank welding process.

An engineering study was conducted to examine the feasibility of Electromagnetic Acoustic Transducer (EMAT) technology for automated inspection of laser butt welds in sheet metal blanks where manual inspection is difficult, due to large blank sizes and automated welding and material handling. The EMAT system used in this study is the first of its kind implemented to inspect laser welded sheet metal blanks. Preliminary production testing results are positive, exhibiting a high correlation between actual defect location and EMAT inspection output.