Heat transfer modeling of the friction extrusion process

The present work is focused on understanding the heat transfer phenomenon and the temperature field in the friction extrusion process. A friction extrusion experiment using aluminum alloy 6061 was designed and carried out, in which the mechanical power input during the experiment was recorded and the temperature variations with time at several key points surrounding the process chamber were measured using inserted thermal couples. A numerical thermal model for the experimental system has been developed. The model includes a rotating extrusion die, a material being processed inside an extrusion chamber, a chamber wall, and a back plate at the bottom of the chamber wall. The experimentally measured mechanical power is used as input to the model to predict the temperature field in the experiment. It is found that the predicted temperature variations at the locations of the thermal couple tips agree well with those measured experimentally, suggesting that the thermal model can serve as a reasonable predictive model for the temperature field distribution in the friction extrusion process.