Tailoring AlSi7Mg0.3 composite properties with CoCrMoNbTi high entropy alloy particles addition via FSP technique

Abstract

The present study summarizes the impact of High Entropy Alloy (HEA) CoCrMoNbTi addition on the microstructure, mechanical properties, and wear behavior of an A356 composite developed using the Friction Stir Processing (FSP) technique. The incorporation of HEAs into conventional alloys has gained attention due to their potential to enhance material performance. In this research, A356 aluminum alloy was subjected to FSP for refining grain structure and improving mechanical properties. The addition of HEA CoCrMoNbTi aimed to further enhance these improvements. The microstructural analysis revealed that the FSP process led to significant grain refinement and distribution of CoCrMoNbTi HEA particles within the A356 matrix for A356/2%Co2%Cr2%Mo2%Nb2%Ti composite. The presence of 2%Co2%Cr2%Mo2%Nb2%Ti HEA particles influenced the solidification process, resulting in modified phase formations and improved grain boundaries and interfacial bonding strength. The number of grains was found to be about 1746.19 per square inch at 500 magnifications for A356/2%Co2%Cr2%Mo2%Nb2%Ti processed composite with FSP. Mechanical testing demonstrated notable enhancements in hardness (67.21 % improvement), and tensile strength (37.10 % enhanced), attributed to the combined effects of FSP and 2%Co2%Cr2%Mo2%Nb2%Ti HEA addition. Furthermore, wear behavior was substantially improved, as the 2%Co2%Cr2%Mo2%Nb2%Ti HEA particles contributed to reduced friction and wear rates.