Comparative study of coated and uncoated tool inserts with dry machining of EN47 steel using Taguchi L_9 optimization technique

摘要

EN47 steel samples are machined on a self-centered lathe using Chemical Vapor Deposition of coated TiCN/Al_2O_3/TiN and uncoated tungsten carbide tool inserts, with nose radius 0.8mm. Results are compared with each other and optimized using statistical tool. Input (cutting) parameters that are considered in this work are feed rate (f), cutting speed (V_c), and depth of cut (a_p), the optimization criteria are based on the Taguchi (L_9) orthogonal array. ANOVA method is adopted to evaluate the statistical significance and also percentage contribution for each model. Multiple response characteristics namely cutting force (F_z), tool tip temperature (T) and surface roughness (R_a) are evaluated. The results discovered that coated tool insert (TiCN/Al_2O_3/TiN) exhibits 1.27 and 1.29 times better than the uncoated tool insert for tool tip temperature and surface roughness respectively. A slight increase in cutting force was observed for coated tools.