ULTRASONIC IN-PROCESS MONITORING AND FEEDBACK OF RESISTANCE SPOT WELD QUALITY

摘要

A method and apparatus for ultrasonic in-process monitoring and feedbac k of resistance spot weld quality uses at least one transducer located in the electrode assembly transmitting through a weld tip into an underway weld. Analysis of the spectrum of ultrasonic waves provides the operator with an indication of the size, thickness, location, dynamics of formation and quality of the spot weld. The method presents a fundamentally new physical approach to the characterization of the spot weld quality. Together with transmission mode it includes new modes of operation of ultrasonic probes su ch as a reflection mode and simultaneous use of transmission and reflection modes, a nd a new physical interpretation of the signal analysis results.