Journal of Materials Science, Vol.30, No.11, 2936-2943, 1995
Evaluation of a Miniaturized Disc Test for Establishing the Mechanical-Properties of Low-Alloy Ferritic Steels
A miniaturized disc test has been used to measure load-displacement curves for a 2 1/4Cr1Mo steel, from which are derived values for the Young’s modulus of elasticity, yield stress and ultimate tensile strength over the temperature range -196 to 25 degrees C. The miniaturized test uses disc specimens 3 mm diameter and 0.25 mm thick and a test jig that applies a load via a 1 mm diameter steel ball at a constant displacement rate. The reproducibility of the method has been determined by testing a large number of the 2 1/4Cr1Mo steel specimens at each temperature considered. Comparisons have been made between analytical and empirical methods of evaluating the tensile yield stress and ultimate tensile strength from the measured load-displacement data. in addition, consideration has been given to the total energy to fracture, K*, and the variation with temperature which confirms a transition from low-energy cleavage to high-energy ductile fracture.