With the aim of quantitative measuring the dynamic adhesive strength of Al₂O₃film/Fe, we use a modified laser spallation setup, and let high-power laser pulse shock the energy absorbing thin coating, then cause a pressure pulse propagating to matrix. At the free surface, a laser probe is used to record the epicentral surface displacement history caused by elastic wave which propagating to the free surface. Though the analysis of elastic wave, data processing and a computer simulation, we propose a novel model of the attenuation and the dispersion of the elastic wave. After characterizing, we obtain a new spallation criteria corresponding to progressive damages at the film- matrix interface, i.e. interface delamination, film spallation and film expulsion, respectively. At the same time, according to the arrival time and attenuation pattern of the elastic wave, we also propose a new computer algorithm for estimating the source fracture dimension.

Date Published: 8 September 1999
PDF: 5 pages
Proc. SPIE 3862, 1999 International Conference on Industrial Lasers, (8 September 1999); doi: 10.1117/12.361105

Published in SPIE Proceedings Vol. 3862:
1999 International Conference on Industrial Lasers
Fuxi Gan; Horst Weber; Zaiguang Li; Qingming Chen, Editor(s)