1988 Volume 52 Issue 1 Pages 103-108
A new method for estimating the strain distribution of deformed metallic surface is proposed as an example of the technical applications of PSEE (photostimulated exoelectron emission) phenomena. PSEE from aluminum specimens placed in a gas-tight chamber under ultraviolet light irradiation was measured with a gas-flow type GM-counter. While a UV spot 0.3 mm in diameter was fixed in the chamber, a sample holder was scanned in the X-direction by a cum and Y-direction by a worm gear. The PSEE intensity was recorded as a function of position with an X-Y recorder. For tensile-deformed aluminum specimens, their nominal strains along their gauge lengths corresponded well to their line profiles of PSEE; i.e., their strain distribution was similar to the PSEE intensity distribution in the case of one-dimentional measurement. PSEE contour maps obtained by two-dimentional scanning also corresponded fairly well to the photographic patterns showing surface strains for both tensile- and fatigue-deformed specimens. The relative change in strain may be easily measured by this PSEE scanning technique, though the strain distribution obtained is not exact in a strict sense.
