Study on improving hole quality of 7075 aluminum alloy based on magnetic abrasive finishing

Abstract

Based on the mechanism of magnetic abrasive finishing, the 7075 aluminum alloy (Al7075) was used in the experimental study. In order to improve wall surface quality and to remove the edge burrs of the hole, a novel magnetic abrasive finishing process was proposed. First, the radial magnetizing pole for the inner surface finishing process was confirmed. The evaluation of magnet spinning speed, abrasive mesh, and abrasive filling amount on the diameter deviation of the hole and surface roughness of the inner wall was studied. According to the characteristics of magnetic abrasive finishing process, Taguchi’s method was used to carry out the test. Through the analysis of variance, the best process parameters were determined and verified. The inner surface roughness was further decreased and the surface morphology was more uniform after finishing process. Second, the edge burr removal process of the hole exit was also studied, and the geometry of the burrs was measured before and after the magnetic abrasive finishing process. The results show that the burrs were significantly removed and the burr removal efficiency was improved by 33.3% compared with the conventional magnetic abrasive finishing process. Finally, the improved magnetic abrasive finishing process is an effective method in improving finishing quality of the Al7075 holes.

Experimental Investigation on Magnetic Abrasive Finishing for Internal Surfaces of Waveguides Produced by Selective Laser Melting

“…For the internal surface, Jiao [23] achieved the deburring of microholes using radially magnetized cylindrical magnetic poles with MAPs. Zhang [24] effectively increased the micro-cutting depth of abrasives by introducing auxiliary magnetic poles for polishing the internal surfaces of high-hardness and thick-walled round tubes.…”

Online monitoring and prediction for surface roughness in rotational electro-magnetic finishing using acoustic emission and vision-based neural network

“…Jiao et al utilized a contact-based stylus profilometer to evaluate finishing efficiency on the inner wall surface of Al7075. According to the offline measurement, the smoothness of the surface was primarily determined by magnetic spinning speed, leading to a 33% improvement in burr removal performance [13]. Singh and Singh improved the surface in the MRF process and provided a theoretical model for achieving a fine surface finish on a cylindrical-shaped component using a stylus profilometer.…”

Development of a New Finishing Process Combining a Fixed Abrasive Polishing with Magnetic Abrasive Finishing Process

“…They reported that using transformer oil or stearic acid liquid can significantly improve material removal rate (MRR), because transformer oil helps to form a physisorption film, and stearic acid helps to form a chemisorption film. Jiao et al [12] applied the MAF process to improve the surface quality of the hole wall and eliminate burrs on the edge of the hole. They used 7075 aluminum alloy as a workpiece, and analyzed the influence of magnet spinning speed, abrasive mesh, and abrasive filling amount on the diameter deviation of the hole and surface roughness of the inner wall.…”