Effect of Strain Rate on the Mechanical Behavior of Additive-Manufactured Aluminum Alloy after Severe Plastic Deformation

This work presents the mechanical behavior of additive-manufactured AlSiMg alloy after severe plastic deformation (SPD). Equal Channel Angular Extrusion/Pressing (ECAE/P) is a well-known SPD method used for mechanical property improvement via grain refinement in metals. In this study, 8 pass ECAP at 250°C ECAP process is conducted on AlSi 10 Mg which is manufactured by laser powder bed fusion (LPBF). Tensile tests were conducted at room temperature and at various strain rates to measure the strain rate sensitivity (SRS). With varying strain rate, there was appreciable change in the flow stress levels indicating that the severely deformed alloy exhibits negative SRS. Possible reasons for this mechanical response are explained based on the evolved microstructure to shed light on the parameters governing SRS in additive-manufactured alloys subjected to SPD.