The influence of severe plastic deformation on the thermal expansion of additively manufactured Ti6Al4V alloy

Abstract

The thermal expansion properties of the Ti6Al4V alloy deposited with direct energy subjected to severe plastic deformation through ECAP were studied in the temperature region 23–700 °C. The deposit samples exhibited two orientations: with the longitudinal axis in the deposition plane and perpendicular to the deposited layers. The microstructure of the deposited alloy and the alloy after thermomechanical treatment was analysed on a scanning electron microscope using the EBSD method. The ECAP process substantially refined the structure of the grains. The temperature dependence of the thermal expansion coefficient estimated for the alloy after ECAP processing exhibited a non-monotonous course. The microstructural changes are the reason for this finding.

Keywords

• Additive manufacturing
• Ti6Al4V Grade5 alloy
• ECAP process
• Thermal expansion
• Dynamic recrystallization