Dynamic Properties of Pre‐Alloyed Molybdenum Steel Powders for Gear Applications

The implementation of PM components in automotive applications increases continuously. Especially applications in heavy-duty components like gears, pistons and connecting rods that are exposed high cycle dynamic loads can be realised with new developed materials and processes [1]. It is known that the dynamic properties of P/M parts are a complex phenomena which are influenced by numerous factors like pores, microstructure, heat treatment, etc. [2]. In several studies it has been proved that the porosity of a P/M part has the greatest influence [3, 4]. It can generally be assumed that raising the density leads to a more or less linear increase of the static mechanical properties, while the fatigue and impact strength increase exponentially [5]. The pre-alloyed Mo-steel powder MSP 3.5 Mo comes very close to meeting the stringent requirements of highly-loaded P/M parts, such as gears.