In the quality assurance of machine components, the socalled finishing and superfinishing processes have important roles. During recent years, the postmachining cold forming methods such as burnishing, shot peening and others have occupied a very important place in industry. Burnishing, which is one of the effective methods used to improve the surface layer properties, is essentially a cold forming process in which the raised microirregularities on the surface layer are plastically moved and pressed into the microcavities. The process is carried out with a highly polished ball or roller type tool which is traversed under force over a rotating work piece. Machines normally used for burnishing operation can be drill presses, lathes, boring machines, and automatic bar or chucking machines. The process of burnishing can be done on parts which are turned, bored, reamed or ground. Any ductile or malleable material with hardness less than 40 HRC can be successfully burnished. Although diamond burnishing machines are available for finishing material harder than 40 HR. the burnishing process is used to improve the shape of components besides producing a good surface finish. Quite the opposite, the burnishing tool will not correct deviations from roundness or Straightness to any degree. In this work an attempt is made to compare the results of ball burnishing (in dry and abrasive paste conditions). The parameters taken in consideration are burnishing speed, burnishing feed, burnishing force, ball material and number of passes. Mathematical models have been developed in terms of surface roughness and surface hardness for ball burnishing process.
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