The Effect of Alloying on Sinter-Hardening Response of Astaloy Mo and Its Diffusion Bonded Derivatives

Paper in proceeding, 2010

In this study, sinter-hardening response of different steel powders based on the Astaloy Mo grade (prealloyed with 1.5% Mo) is investigated. In order to understand the effect of alloying, Astaloy Mo was compared to its diffusion bonded derivatives; which are benefiting from an additional 2 wt.% copper (i.e. Distaloy DH) and 2 wt.% Ni (i.e. Distaloy DC). Tensile specimens of each alloy containing 0.55-0.7 wt.% admixed graphite were prepared. All specimens were sintered at 1120°C for 30 minutes and cooled at a rate of 2.5°C/s within the range of 800 to 300°C. Subsequently, the sinter-hardened specimens were stress relieved at 200°C for 60 minutes. Using X-Ray diffraction technique the residual stresses of all specimens were analyzed. In order to understand the relation between microstructure and the obtained mechanical properties, tensile testing and metallographic investigations were performed.