<![CDATA[This study was designed to explore the effects of varying amounts of Nickel (Ni) and Chromium (Cr) on the mechanical, microstructural, corrosion, and machining properties of Al5Si3Cu alloy. Samples were prepared using a sand-casting method with Ni-Cr additions ranging from 2g to 10g, and analysed using spectroscopy, mechanical testing (hardness, tensile, impact, and compression), machinability evaluation, and wear testing via pin-on-disc. The evolved microstructure was observed using X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM), while corrosion resistance was investigated using potentiodynamic polarisation. The results revealed that Ni-Cr additions led to a complex balance of effects. While corrosion resistance improved at 8g Ni-Cr, mechanical strength and machinability declined due to the formation of brittle intermetallic compounds. Wear resistance was highest at 2g Ni-Cr but deteriorated with higher additions. At 10g Ni-Cr, corrosion resistance and overall performance declined due to oversaturation and microstructural defects. It was concluded that varying percentage of Ni-Cr has different effect on these properties of the ternary alloy. However, excessive alloying resulted in embrittlement and reduced performance. The findings emphasise the importance of precisely controlling Ni-Cr content in aluminium alloys to achieve a desirable balance of properties. Future research should focus on composition optimisation and understanding intermetallic behaviour.]]>
