Performance studies of multilayer hard surface coatings (TiN/TiCN/Al2O3/TiN) of indexable carbide inserts in hard machining: Part-II (RSM, grey relational and techno economical approach)

► Machinability study in hard turning using inexpensive coated carbide insert. ► Inappropriate selection of process parameter may cause excessive tool wear and surface roughness. ► RSM model proposed are statistically significant and adequate for flank wear and surface roughness. ► The optimal parametric combination is d1-f1-v3 and improvement of GRG is found to be 0.3093. ► Measured tool life at optimal level has been found to be 47 min and machining cost per part is only Rs. 3.17.