Parameter optimization of creep feed grinding for inconel 939 super alloy

Gas turbine components used in the aviation industry are subjected to serious loads. The turbine blades located in the hot section are suffered from dynamic loads and thermal stresses caused by high temperature and centrifugal motion. Therefore, turbine blades must be produced in a way that can be easily separated, replaced, and reassembled from the rotor disc. However, in order to withstand high loads, production should be done with narrow tolerances without damaging the surface integrity. Therefore, milling, wire electrical discharge machining, creep feed grinding are used in the aviation industry. In this study, the root geometry that connects the turbine blade to the turbine rotor disc is processed. The studies are carried out by considering the surface roughness, profile tolerances, the thickness of recast layer and heat affected zone, which affect the surface integrity. In this study, creep feed grinding is investigated by Taguchi method using different parameter sets for continuous and non-continuous states. The two different types of creep feed grinding are examined with parameters such as depth of cut, table feed rate, wheel linear speed, and the dressing ratio rates. As a result of these investigations, it is observed that the parameters have an effect on the surface integrity and that they affect each other in the results such as recast layer and surface roughness. Finally, optimum parameters based on the geometry depends are obtained for the production of turbine blade fir tree with creep feed grinding.