Fatigue Properties of Diffusion-bonded Molybdenum Steel Powders for High Strength Applications

摘要

Previous studies have shown that materials manufactured from a Fe1.5Mo-4.00Ni-2.00Cu diffusion-bonded steel powder exhibit very good static properties. Further investigation has been undertaken to optimise the alloying system. A diffusion-bonded steel powder has been developed with a lower content of alloying elements (Fe1.5Mo-2.00Ni-1.00Cu). The high-alloyed and low-alloyed materials have been compared. Very similar static properties after sintering and rapid cooling have been found. The objective of this study was to compare the influence of different sintering conditions, cooling rates and heat treatment conditions on fatigue properties on the two different alloying systems. These materials are characterised by their excellent fatigue properties which are more than 30% higher than those achieved using the more conventional diffusion-bonded Fe-0.5Mo-1.5Cu-4.0Ni grade. These improved fatigue properties allow the manufacturing of PM parts that are exposed to high dynamic loads.