An experimental study on chemical corrosion-assisted magnetic abrasive finishing of SLM Co-Cr-Mo alloy

Abstract Alloys have many advantages over pure metals, but in most cases, it is difficult to get a proper surface due to various factors. To solve the problem of poor surface quality, the surface of cobalt-chromium-molybdenum (Co-Cr-Mo) alloy formed using selective laser melting (SLM) was investigated by chemical corrosion-assisted magnetic abrasive finishing (MAF). First, Co-Cr-Mo alloy was formed by the SLM method, the heat-treated forming parts were chemically etched with a mixture of HCl: H2O2 = 1:1, etched for 5 min, and then MAF tests were carried out; respectively. The response surface approach was employed to finalize the experimental setup, which resulted in the specification of MAF's operational parameters. These included a spindle speed of 1050 revolutions per minute, a machining clearance of 1.8 millimeters, and a feed speed fixed at 15 millimeters per minute. The experimental outcomes indicate that the initial specimen exhibits a surface roughness measurement of approximately 6.5 micrometers, the roughness after chemical corrosion is reduced to about 0.7 μm, and the roughness after magnetic grinding is reduced to 0.070 μm. It can be seen from the two-dimensional contour, three-dimensional topography, and image effect diagram that the unfused powder and burrs adhering to the surface of the sample are removed, the sample obtains a good residual stress state, and the corrosion resistance is improved.