Study on material removal mechanism of photocatalytic-assisted electrochemical milling-grinding SiCp/Al

Silicon carbide-reinforced aluminum matrix composites (SiCp/Al) are widely used in aviation, automobile, electronics, and many other fields due to their excellent comprehensive material properties. However, traditional processing technology faces severe challenges. This paper proposed a novel hybrid processing method of SiCp/Al materials, photocatalytic-assisted electrochemical milling-grinding (PAECMG). In this method, the photocatalytic reaction layer on the surface of insoluble SiC particles is removed by repeated grinding. The removal mechanism of anode material SiCp/Al in the PAECMG process was studied in detail by experiments. The abrasive tool destroys the passivation layer on the workpiece's surface to accelerate the aluminum matrix's anodic dissolution. Moreover, the SiC-reinforced particles are repeatedly and alternately removed by photocatalytic reaction and grinding mechanical action. Microscopic surface contrast analysis demonstrated that PAECMG could simultaneously remove metal aluminum matrix and silicon carbide particles. Comparing current waveforms during machining shows that PAECMG can improve machining stability. Based on the detailed analysis of the material removal phenomenon, a qualitative model of the material removal mechanism of PAECMG was established. This study provides valuable insights into the material removal mechanism in the combined photocatalytic-assisted ECM and mechanical grinding process.

Automated summary

This paper proposes a novel hybrid processing method, photocatalytic-assisted electrochemical milling-grinding (PAECMG), for SiCp/Al materials. The surface photocatalytic reaction layer and the passivation layer on the aluminum matrix are removed by grinding, while the SiC-reinforced particles are alternately removed. This method improves machining stability.