Study on Abrasive Flow Polishing Process of Aluminum Alloy and High-temperature Alloy Microchannels by SLM Additive Manufacturing

The metal additive manufacturing technology represented by the laser selective zone melting (SLM) technology makes the surface of the products very rough due to the inherent "powder adhesion" and "spheroidisation effect", which makes it difficult to meet the usage requirements. Facing the rough bore surface of SLM microfluidic channel, we adopt the abrasive flow polishing technology to polish the inner surface of AlSi10Mg and GH4169 microfluidic channels prepared by SLM, and investigate the effect of abrasive flow process on the surface roughness and dimensional accuracy of microfluidic channel bores. The results show that after the abrasive flow treatment, the surface qualities of the bores of both the aluminium alloy and high temperature alloy fabricated by SLM additive manufacturing are effectively improved, and the roughness of the micro-runner bore surface decreases by more than 50 %. The surfaces of the runner bores are clean with no attachments. There is no large change in the runner dimensions, and the dimensional accuracy is retained at a relatively high level. Therefore, the abrasive flow process is an effective polishing technique for SLM additive manufacturing of micro-runner structure parts.