Study on the Surface Modification Using Laser Roughing and Fe-Based Powder Plasma Spraying for AlSi9Cu3 (Fe) Alloy

Abstract

In this paper, the surface modification for Al alloy cylinder block (AACB) was investigated in order to improve the surface properties of AACB inner wall. It is found that the laser roughing process can increase the contact area, thereby modifying the morphology of the interface between layer and matrix and improving obviously the bonding force. The properties, including strength, hardness, heat resistance and wear resistance, were improved mainly due to the Fe-based powder plasma spraying process. Owing to the combination of laser roughing and plasma spraying, low porosity of the layer was obtained, enabling the surface to hold a certain amount of lubricating oil, leading to the improvement in engine performance. Via the analysis of microstructure, hardness, mechanical properties and machining dimension, it is suggested that the combination of laser roughing and plasma spraying can act as a feasible way to tailor the properties of surface layer and provide great potential to improve the practical applications of AACB in the field of automotive industry.