Parametric Investigations into Internal Surface Modification of Brass Tubes with Alternating Magnetic Field

The final finish operations have great significance in an overall manufacturing cycle of a product. The surface finishing and modification of surfaces have been the vital requirements of most of the products. The processes like shot peening, shot blasting, abrasive finishing and super finishing are being largely employed for such requirements. While final finishing of flat and outside surfaces are relatively easy and well established, the internal surfaces such as those of pipes is not so simple. In this paper, the application of low frequency alternative magnetic field has been explored for imparting surface modification including surface on the internal cylindrical surface. The cold drawn SUS304 stainless steel (SS) pins have been used as micro tools. The interaction of vibrating SS pins (due to AC magnetic field) with internal surface of rotating pipe has resulted in micro indentation of surface thereby improving surface characteristics. An experimental setup has been developed to investigate the effect of major process parameters on the percentage improvement in surface finish and surface hardness. Response Surface Methodology has been employed to design the experiment for demonstrating the effect of various process parameters on the surface finish and hardness of the processed surface. It is observed that SUS304 stainless steel pins are capable of improving the surface characteristics like surface finish and surface hardness in the internal surface of brass tube.