Determination of residual stress fields beneath a Vickers indentation using photoelasticity

Static Vickers indentation tests were performed on Homalite specimens with an intent to obtain the residual stress distribution beneath the indentatio n. The indented specimens were placed in a circular polariscope to view the fringe patterns corresponding to the induced residual stress. Similitude a nalysis was later employed to identify the functional relationship between the various parameters related to an indentation test. The analysis resulte d in a unified relationship that can assist in the determination of residua l stress in nontransparent materials subjected to similar geometric and loa ding conditions. The shear stress contours provided here can also be used a s guidelines to verify constitutive models under complex three-dimensional loads.