Experimental measurement of thermal diffusivity, conductivity and specific heat capacity of metallic powders at room and high temperatures

Abstract

Because of the complications associated with metal additive manufacturing process, comprehensive modeling is done to improve the process. Thermo-physical properties such as heat capacity, thermal conductivity and diffusivity of metallic powder is very crucial for the models to be accurate. Due to challenges associated with measuring these properties at high temperature, available analytical models are often used to determine these temperature dependent thermo-physical properties. This study is conducted to fill this gap and provide experimental information that has been missing from the bulk of the literature for variety of metallic powders commonly used in additive manufacturing processes. Additionally, a comparison between these experimental data and analytical models are conducted to determine the correlation and accuracy of these models. Analysis revealed that all the thermal properties of the powders show a non-monotonic behavior at high temperature. A regression analysis is conducted to predict thermal conductivity at higher temperatures.