A Time-Compressed Computational Approach for Thermal Analysis of Preheating Process in Powder Metallurgy

Thermal properties of powder material/particulate media differ significantly from bulk macroscopic/continuum properties. Preheating metal or superalloy powders can take place for several hours depending on homogenization, densification and green strength required for further processing and application. Finite element simulations for these long thermal cycles are generally complex and time consuming. This paper provides a computational time compressed approach using finite element software DEFORM ™ by modifying thermal parameters based on theoretical relationship linking bulk properties to powder as a function of density. A comparison is done between fully dense material with powder thermal properties and porous material with bulk thermal properties to analyze the effect of these parameters on functioning of computational model. The influence of thermal conductivity and heat capacity on time-compression approach is also investigated. The results obtained using time compression approach are compared to standard numerical simulations that replicate thermal evolution during the preheating process.