Research on internal surface finishing of multi-cross channels

Abstract

The quality of the internal surface plays a crucial role in the performance of parts with complex structures, which are widely used in aerospace, biomedical, and other fields. However, due to poor accessibility, the uniformity of the internal surface of multi-cross channels are low after finishing with existing methods. To address this issue, this paper proposes a step-by-step abrasive flow machining method according to the characteristics of multi-cross channel structures. By flexibly setting the positions of inlets and outlets and adjusting finishing parameters in each step, the material removal rate in different sections of the multi-cross channels can be regulated. Guided by simulation results, the material removal rate in each section becomes consistent after successive steps, achieving uniform finishing of the entire channel. To verify this method, a separatable stainless-steel part with six crossed channels was finished under an inlet pressure of 10 MPa for 40 minutes by using SiC abrasive with a size of 75 μm. The internal surface roughness of the workpiece was reduced from 1.919 μm to less than 1 μm, with variation in each section controlled to less than 12%.