Characteristics and effects of particle morphology and tensile ductility resulting from FSP of Al-Si-Cu-Ni casting and forging piston

The aim of this work was focused exclusively to clarify the diversification of tensile ductility between the friction stir processed (FSPed) casting and forging Al-Si-Cu-Ni heat resistant piston alloy. Experimental results show that though a single-pass FSP can improve tensile ductility of hot forging piston alloy, but still not enough to achieve sufficient refinement. Microstructural refining and homogenization will play an important role on the variation of tensile properties, also governed by the particles dissolution effect of Al ₃CuNi (δ phase) after performed friction stir process resulted in disappearance of the potential nucleation sites for precipitation. The present investigations through conducted different combination of abovementioned casting, extrusion-forging and FSP process to verify the variation of tensile deformation behavior and tensile ductility.