Ti sheet: The effect of gage length and width measurement on plastic strain ratio

The effect of gage length, width measurement locations, and axial strain on plastic strain ratio have been investigated for commercially pure titanium sheet. The specimens were ASTM E 517-92a subsize, type A, and type A alternative. In general, slightly larger length strain values were observed for shorter gage marks. Because of differences in strains of gage lengths and width locations for each specimen type, the magnitude of the calculated R-value depends on the gage length and width measurement locations. Also, for a given gage length and width measurement location, the magnitude of the calculated plastic strain ratio and its variation with axial strain depends on specimen type. The type A specimen resulted in fewer changes in R-value with increased strain than either the subsize or type A alternative specimens.