Ring-compression tests on sintered iron preforms

Abstract

Standard ring-compression tests have been carried out on sintered iron preforms of different initial densities. The values of the apparent strength coefficient and the strain hardening exponent have been estimated to identify which conditions of the perform result in mechanical properties closest to those of equivalent wrought part. The coefficient of friction has also been estimated for compacts as well as for wrought parts, so that near identical frictional conditions could be employed for comparison purposes, in computations of their respective force requirements. Compacts of different length-to-diameter ratios have been prepared for different compacting pressures and the optimal conditions of the billet geometry for the least non-uniform densification along the length of the compact have been established. The main aim of this fundamental work was to prepare, and explore the properties of, sintered preforms of different initial densities and of greater length-to-diameter ratio so that future cold Hooker studies on these compacts would be possible.