Ductility improvement of Ni-added molybdenum compacts through the addition of Cu and Fe powders

摘要

The sintered density of molybdenum can be significantly improved through the addition of a small amount of nickel. However, such addition impairs the ductility due to the formation of a NiMo intermetallic compound at the grain boundaries. This makes the plastic deformation process, such as rolling, drawing, and forging, impossible. This study shows that when copper is added, the sintered density can be further increased, but, not the ductility. This ductility problem of the Mo-Ni-Cu system can be improved when a small amount of iron is added and when the total amount of the alloying Ni, Cu, and Fe is over 6wt percent, such as in the Mo-JNi-lCu-lFe system. Such improvement is attributed to the elimination of the brittle NiMo compounds in the matrix.