MATHEMATICAL MODELING OF HEAT TREATING POWDER METALLURGY STEEL COMPONENTS

A mathematical model to predict the response of powder metallurgy steels to heat treatment is presented and discussed. The model is based on modification of commercially available software that was originally developed for wrought alloys so that it can account for the effect of porosity. An extensive database had to be developed specifically for PM steels and includes porosity- and temperature-dependent phase transformation kinetics, and porosity- and temperature-dependent phase-specific mechanical, physical, and thermal properties. This extensive database has been developed for FL-4065 PM steel and has been used in the model to predict dimensional change, distortion, and type and quantity of metallurgical phases that develop in a typical PM component upon heat treatment. The model predictions are compared to measured values and are found to be in excellent agreement with them