A Decade of Experience With Small Specimen Testing to Evaluate Mechanical Properties of Materials

Abstract

Small specimen testing has become popular in the recent times, due to the need for material property evaluation using limited volume samples available from processing techniques, scoop extraction of materials. There are several methods of direct and in-direct mechanical property evaluation such as: automated ball indentation, miniature tensile testing, small punch testing, shear punch testing and miniature specimen impact testing. Most of these techniques provide a correlation with standard specimen test data through empirical relationships. This paper summarizes work done at the author’s Institution during the last decade on small specimen testing, with specific reference to spherical ball indentation (both static as well as cyclic indentation), shear punch and small punch testing on a number of metallic materials. Specific examples of how the material degradation due to prior damage (plastic deformation, fatigue, creep) are discussed.