AN EXPERIMENTAL INVESTIGATION ON THE EFFECT OF THICKNESS OF SPECIMEN IN SMALL PUNCH TEST FOR SUS304 STAINLESS STEEL

Abstract

The small punch test is considered as a reliable testing method for evaluation of mechanical
properties of metal materials. In this study, small punch tests were performed by a conventional tensile
testing machine for specimens with different thicknesses made from SUS304 austenitic stainless steel.
The yield strength criteria of the material are calculated from the applied force - deflection relationship.
From the calculation results, it shows that the yield strength calculated by the small punch test depends
considerably on the size of the specimen. When the thickness of specimen is 0.5 mm, the results are
very close to the yield strength calculated from the tensile test. Meanwhile, the results for specimens of
other thicknesses have large differences due to the influence of the ratio between the size of the
specimen and the size of the jig.