Abrasive jet polishing on SKD61 mold steel using SiC coated with Wax

Abstract

This study investigates the abrasive jet polishing (AJP) of electro-discharge-machined and ground SKD61 mold steel specimens using #2000, #3000 or #8000SiC particles and compound additives comprising either pure water, pure water and water-solvent machining oil, or pure water and water wax. The results show that when the polishing process is performed using #2000SiC particles with a pure water and water wax additive, the surface roughness of the electro-discharge-machined SKD61 surface is reduced from Ra: 1.0 μm to 0.08 μm within 90 min. Polishing the ground SKD61 surface using #3000SiC particles with pure water and water wax, the surface roughness is found to reduce from an initial value of Ra = 0.36 μm to a final value of Ra = 0.054 μm within 60 min. To improve the polishing performance, a gas atomization technique is employed to fabricate wax-coated #3000SiC particles. The results show that when polishing is performed using these wax-coated particles and a compound additive of pure water and water wax, the roughness of the ground surface is from Ra: 0.36 μm to 0.049 μm within 45 min. Overall, the results show that the use of wax-coated abrasive particles reduces the polishing time and achieves an improved surface finish.