Measurements of Strain-Rate Distributions on Material After Shpb Impact

We have proposed a sophisticated novel method of the SHPB experiment to measure
the local strain-rate distributions on a surface of the specimen by using mechanoluminescent
materials combined with a high-speed camera and an image intensifier. The feasibility study
was made for the aluminum specimens pasted by a typical mechanoluminescent material -Eu
doped SrAl2O4 film, in order to obtain the fundamental data for the method. Our results
showed that SrAl2O4: Eu emitted lights as a response to the stress. Increase of the light
intensity was swift enough to follow the strain change due to SHPB impact. The luminescence
intensity was experimentally verified and expressed as a product of strain and strain rate.
Accordingly, it can be said that this method gives a good tool for measuring time variation of
local strain distributions.