Cutting forces and surface roughness in hard turning of hot work steel X38CrMoV5-1 using mixed ceramic

Abstract

The aim of this work is to evaluate cutting forces and surface roughness in hard turning of hot work steel X38CrMoV5-1 [AISI H11].This steel is hardened to 50 HRC, machined by a mixed ceramic tool (insert CC650 of chemical composition 70%Al2O3+30%TiC), free from tungsten on Cr-Mo-V ba-sis, insensitive to temperature changes and having a high wear resistance. It is employed for the manufacture of highly stressed diecasting moulds and inserts with high tool life expectancy, plastic moulds subject to high stress and forging dies.The tests of slide-lathing were carried out accord-ing to the method of planning experiments. The results made it possible to study the influence of cutting variables (feed rate, cutting speed and depth of cut) and flank wear (VB) on cutting forces and surface roughness. Mathemati-cal models were established to express the influence de-gree of each cutting regime element on the studied techno-logical parameters. Thus, the ranges of the best cutting conditions adapted, were given.This study confirms that in dry hard turning of this steel and for all cutting conditions tested, the major force is the thrust force and the found roughness criteria are close to those obtained in grinding.