Experimental Study of Thermal Contact Conductance of Tool-Sample Interface After Heat Treatment

Abstract

Heat transfer across the metallic interface plays a vital role in metal forming processes for the better design of tools, dies, and other components. Thermal contact conductance (TCC) is the parameter which relates the interfacial heat transfer and interface temperature. Heat treatment is the process commonly employed to improve the thermo-mechanical properties of a material. Thus, the effect of heat treatment on the tool-sample contacts is the main objective of this work. Here, experiments are performed to investigate the thermal properties at the tool steel–mild steel contacts with and without heat treatments. Experiments have been performed on a simple experimental setup which is based on axial heat flow method. The experiments have been conducted under atmospheric environment and varying loading and heat flux conditions so as to study the contact heat transfer for a range of contact pressure and interface temperatures. Steady-state methodology is employed for estimating thermal contact conductance at the joint of two specimens. Heat treatment of tool steel and mild steel specimens has been carried out using normalizing process. Eventually, the combined effect of hardness and thermal conductivity of the tool steel and mild steel on thermal contact conductance has been presented with varying contact pressure and temperature conditions. Moreover, results of TCC have been presented in normalized form to study the combined effect of different parameters and comparing with the pertinent literatures.