Study of the effect of roller burnishing process parameters on surface roughness and micro hardness of cast iron parts.

Due to the needs of different industries to produce high precision dimensional products and desirable surface properties and the highest effect of final surface quality on product performance, selection of effective and suitable polishing processes for production of quality products is important. Among different methods of polishing, the burnishing process due to low cost, the possibility of installation on different machines and the polishing without chip has been consideration. Therefore, in this study, due to the widespread application of ductile cast iron in various industries, after preparing the samples of ductile cast iron, making the roller burnishing tools and mounting it on the lathe machine, experiments were carried out in accordance to experimental design table and the effect of burnishing force, feed rate and number of passes, on microhardness and surface roughness of samples were evaluated. For statistical analysis, the results of minitab software and response surface methodology (RSM) were used and the statistical analysis performed with the confidence level of 95%, the most effective parameters and their desirable values to increase the microhardness and quality of samples were introduced. The results showed that the effect of the burnishing force, had the greatest impact on the microhardness and roughness of samples and the optimization of samples by (RSM), optimum value for surface roughness and microhardness of specimens, respectively, 0.562 μm and 203.20 Vickers were obtained in comparison with the values for the initial sample, the surface roughness of samples about 58% reduction and microhardness of samples were increased about 12%.