Study of the thermophysical properties of heat-resistant intermetallic titanium γ-alloy obtained using methods of shaped casting and additive technologies

Abstract

Nowadays, the transition from shaped casting to the methods of selective laser sintering and selective electron beam sintering (SELS) has been implemented for a number of materials. The thermophysical properties of materials play a decisive role when designing and modeling heat and mass transfer processes during powder sintering by additive technologies and monitoring the stability of the operational properties of final products. We present the results of studying the thermophysical properties of the samples of heat-resistant intermetallic titanium γ-alloy obtained by shaped casting and SELS in the range of 200 – 900°C. The characteristic DSC curves of the images and experimental temperature dependences of the heat capacity and thermal conductivity are presented. Comparative analysis of sample density measurements was carried out before and after thermal exposure. Analysis of the results obtained revealed a similar nature of the temperature dependences of the specific heat capacity and thermal conductivity of the samples produced by the methods of shaped casting and SELS. The presence of thermal stresses was observed when measuring the thermal expansion coefficient in the samples obtained by shaped casting. However, leveling of the stress state by additional thermal exposure led to identical values of the thermal expansion coefficient for the samples obtained by both methods. The results obtained can be used to improve the methodology for modeling heat and mass transfer processes during sintering of metal-powder compositions.