Effect of Chromium Addition on ZA40 Alloy Fabricated by Powder Metallurgy Method

This study aims to develop chromium particle-reinforced ZA40 metal-metal composites via the powder metallurgy route and to investigate the influence of varying chromium content on their microstructural and mechanical properties.Composites containing 5 wt.%, 10 wt.%, and 15 wt.%Cr were fabricated to evaluate the effect of reinforcement content.The ZA40 matrix and chromium powders were homogenized by ball milling for five hours, followed by hot pressing at 500 C under a pressure of 500 MPa in an argon atmosphere for two hours.The resulting composites were characterized in terms of microstructure, hardness, density, and tensile strength.The results revealed that increasing chromium content led to higher porosity and a corresponding decrease in relative density.Notably, the composite containing 10 wt.% Cr exhibited the highest hardness (182 HB) and tensile strength (240 MPa), indicating an optimal balance between reinforcement and structural integrity.In contrast, excessive Cr addition (15 wt.%) resulted in deteriorated properties due to increased porosity.Overall, the findings suggest that the incorporation of Cr particles into the ZA40 matrix significantly enhances mechanical performance, particularly at an optimal Cr content of 10 wt.%.These results highlight the potential of ZA40-Cr composites as cost-effective and high-performance materials for structural and engineering applications.