Investigations into hard turning process using wiper tool inserts

Abstract

Now a day, major objectives of industries are to increase productivity and quality of product at low cost with minimum energy consumption which in turn lead to economic and eco-friendly manufacturing. Hard turning with the tool having wiper geometry possess these advantages over conventional turning process followed by grinding process. Hard turning is a primary metal cutting process which is extensively used for reduction of the diameter of workpiece to specified dimension and generation of smooth surface finish on the workpiece material having hardness greater than 45 HRC without supplementing it with grinding. Wiper geometry technology which is used for hard turning operation is made by carefully developed series of radii which make up the cutting edge. In conventional insert, nose of the edge has only one radius while in wiper geometry, wiper cutting edge has large main radius complemented by a number of smaller radii. Materials used for hard machining are hardened alloy steel, tool steels, case hardened steels, Inconel, nitride irons, hastelloys, Hadfield steel, hard chrome coated steels and heat treated powder metallurgical parts etc. While the cutting tool material used for hard turning are coated carbide tool, tungsten carbide, ceramics, CBN, PCBN etc. Few researchers have identified that efficient turning of material having high hardness is achieved through proper selection of process parameter to minimise surface roughness and cutting forces and for this optimization of process parameter is required available conventional and non-conventional optimization processes. Process parameter for hard turning are cutting speed, feed rate, depth of cut, cutting angle, hardness of workpiece, diameter of workpiece, nose radius of tool etc. while output parameter are surface roughness, material removal rate, energy consumption etc. While other researchers have used numerical techniques like Finite Element method to perform various analysis like thermal, vibration, buckling, stress and modal analysis related to hard turning. It is felt that a comprehensive review is required to identify the challenges exist in hard turning using wiper geometry tool and measures needed to overcome them. This paper presents a study of such research contributions, mechanics of material removal, finite element analyses, associated challenges and possible remedies related to hard turning with wiper geometry tool so as to propose a guideline for fresh researchers and practising production engineers.