(10)INFLUENCE OF THE PARTICLE SIZE DISTRIBUTION AND MORPHOLOGY OF NI AND CU POWDERS ON THE DIMENSIONAL CHANGE OF SINTERED PARTS

摘要

Dimensional change is one of the most important properties of PM structural parts and part producers are demanding tight tolerances. Copper and nickel elemental powders are commonly used as admixed additives to tailor targeted properties but both result in a significant dimensional change. Both elements generally increase the mechanical properties but copper is known to promote growth while the use of nickel leads to shrinkage.This paper focuses on the impact of characteristics of copper and nickel additives on the properties of the resulting PM parts and particularly on dimensional change. The particle size distribution (PSD) and the morphology of different types of Cu and Ni additives were characterized and the link between these characteristics and the dimensional change was investigated under slow cooling rates.