Influence Of 3D Complex Grooves On Cutting Performance Of Coated Inserts For Stainless Steel

Stainless steel has been widely applicated in the field of petroleum, chemical industry, aerospace, construction and so on because of its special physical-mechanical properties. However, there are also some disadvantages existing in the processing of stainless steel such as terrible work hardening, chip adhesion, difficulty in chip-breaking, severe abrasion which are resulted from some of its characteristics such as high plasticity, high toughness and poor thermal conductivity. Those disadvantages will lead to poor cutting performance and influence the surface quality of workpieces and lifespan of inserts. The chip-breakers are usually settled on the rake face of turning inserts used in modern cutting process. The cutting performance of the inserts can be remarkably improved by reasonable design of the groove’s structure.This paper researched into the cutting performance of inserts with M type 3D complex grooves used in cutting stainless steel. The influence of groove’s key geometric parameters on chip-breaking performance, cutting forces and chips’deformation of M type inserts were analyzed by experiments.Orthogonal chip-breaking experiments on inserts with different kinds of grooves were carried out to analyze the influence of processed materials and groove’s geometric parameters on chip-breaking performance. The groove’s key geometric parameters were found out which had the biggest influence on chip-breaking performance. Contrast experiments between M type rough machining and semi finish machining inserts were carried out to compare the differences in chip-breaking performance and also analyze the reasons of those differences.A cutting force measuring platform was built to analyze the difference of cutting forces among different kinds of grooves by changing the cutting parameters. The finite element analysis of cutting process with different kinds of grooves were conducted by using the software Abaqus. The mathematical models of the main cutting force on groove’s key geometric parameters under the certain cutting parameters were built which were prooved to be right. In combination with the production practice, the selection of key groove geometric parameters was put forward under the premise of ensuring good chip-breaking performance as well as smaller cutting forces.The metallographic samples were made out of the chips coming from some chip-breaking experiments to conduct the micro metallographic analysis of serrated chips. The relationship between chips’deformation degree and cutting force as well as groove’s geometric parameters was analyzed by measuring and calculating the correlated parameters of serrated chips’segments.