Improvement of Surface Quality of AISI 1010 Steel Plates by Ball Burnishing

Ball burnishing has been an effective surface finishing process that generally requires pressing hardened steel rolls/balls, during feed motion, into the surface of the metallic workpiece. The purpose of this study is to examine the improvement of the burnished surface quality by optimizing several burnishing factors, including ball diameter (d), depth of penetration (p), number of passes (N) and type of lubricants (L) for improving surface quality of AISI 1010 steel plates. A second-order mathematical model is developed to predict the surface quality as functions of ball burnishing parameters. The optimal burnishing parameters were determined by conducting central rotatable design matrix experiments and predicting the response models for the surface roughness and hardness. The optimal burnishing conditions for the steel plates were found by using a ball diameter of 12 mm, a burnishing depth of 0.25 mm, a number of passes of 5 and 15W-40 (L3) for the type of lubricant. With these optimal parameters, the mean surface roughness is reduced from R_a = 2.48 to R_a = 0.37 µm, while Brinell hardness increases from 59 to 70.88 HRB. The results show that all lubricants used in this study had negligible effect on the surface hardness.