Force-to-Stress Conversion Methods in Small Punch Testing Exemplified by Creep Results of Fe-Al Alloy with Chromium and Cerium Additions

Abstract

Application of the small punch test in technical practice is critically dependent on the existence of reliable methods for conversion of data measured by means of such a biaxial test to equivalent quantities of uniaxial tests. In the paper, various methods for recalculation of force in small punch test to stress in conventional creep test are investigated. The methods include: (i) classical CEN Workshop Agreement model, (ii) empirical force to stress conversion method, (iii) modified Chakrabarty method and (iv) constant deflection rate method. The methods are examined using the data obtained by testing Fe-Al based alloy with additions of chromium and cerium. The tested alloy enables verification of conversion methods for different crystallographic lattices, namely D03 at lower temperatures and B2 at elevated temperatures.