EFFECT OF MO, NI, CU AND GRAPHITE CONTENTS ON THE PROPERTIES AND ECONOMICS OF ORGANIC-BONDED POWDERS USED IN HIGH PERFORMANCE PM APPLICATIONS

摘要

Numerous PM parts are produced with diffusion-alloyed powders of various chemical compositions and more particularly with the MPIF designated grade FD0400 (0.5Mo-4Ni-1.5Cu). However, the rising price of alloying elements over recent years, coupled with the constant requirement to produce high performance parts at the lowest possible cost, have forced the powder producers to develop cost effective alternatives or other types of alloys. In this regard, organic-bonded powders produced with the binder-treatment FLOMET technology have been introduced as a cost effective alternative to diffusion-alloyed grades. Moreover, a major advantage of this organic-bonding technology is its great versatility. Indeed, it is very easy to modify the formulation by changing the base powder grade and/or the level and grade of Ni and Cu in order to better meet application needs at the lowest possible cost. In order to take full advantage of the great flexibility of the organic-bonding technology, a good understanding of the effect of mix formulation on mechanical properties and costs is required. This paper presents the results of a study evaluating the effect of Ni, Cu, graphite and pre-alloyed Mo levels on the properties of organic-bonded powders similar to the MPIF diffusion-alloyed grade FD0405 (0.5Mo-4Ni-1.5Cu). The effects of each factor on the properties are quantified as a function of their relative effect on cost. Using the results of this study, a model was developed predicting the formulation required to obtain a particular set of desired sintered properties at the lowest possible cost. Properties of optimized leaner versions developed with that model are also presented.