Experimental investigation of the effect of surface roughness of the material hardness forming machining.

Required for the intended use of the steel hardness, ductility, macro and microgeometry shape features are important for design. Forming various heat treatment is performed and is then applied first to achieve these properties. As a result of heat treatment resistance, ductility, hardness is provided, but are faced with distortions and deformations. The difference can be corrected in the grinding geometry made so as not always possible. The application of standard machining AISI forming process without heat treatment AISI/SAE 8620 steel, carburized surface of the liquid was adjusted to HRC 59 hardness and then macro machining shape by shaping the microgeometry and geometric surface was obtained. The resulting micro-geometric surface unevenness was measured and was found to 0.322 μm. Hardness of investigation in shaping metal removal machining of steel and optimization variables were determined using high L8 experimental design method. Depth of 0.2 mm as the optimum operating condition, feed rate 0.15 mm/rev, rotation speed of 3000 rev /min, respectively. Keywords: Surface roughness, hardness, machining, forming, experimental design.