The influence of process conditions on the structure and properties of P/M oil pump rotor

One of the typical examples of powder metallurgy (P/M) product is rotors used in oil pumps. PM provides the unique, cost effective mass production method for the intricate shape components. This thesis presents a comparative evaluation of the microstructure and mechanical properties of P/M rotors processed in a range of sintering atmospheres. The processing atmosphere had a significant effect on the microstructure and mechanical properties of this automotive oil pump component. A combination of scanning electron microscopy (SEM), energy dispersive spectrum (EDS), image analysis was used for the identification of the structure of the oil pumps. The microstructure of the sintered rotor components generally consisted of interconnected network of iron particles. In order to optimise the overall properties of P/M rotors, examination of the structure along the tooth region was realized and sintered components in different carbon potential atmospheres were subjected to wear tests to specify wear ratios.