Wear Behaviour of Carbide Tool During Machining of Steel

Abstract

Wear process takes predominant role in reducing the tool life during machining of steel. Tool wear is the progressive loss of material from the surface of the body of a tool. This occurs as a natural consequence when two surfaces with relative motion interact with each other. Challenges of wear mechanisms such as variation in chips, high pressure loads and spring back are responsible for tool wear. In addition the rate of tool wear depends on tool and work piece materials, tool shape, cutting fluids, process parameters (such as cutting speed, feed rate and depth of cut) and tool geometry and machine tool characteristics. The tool wear weight assesses real damage to the tool and is also based on blended wear of flank, crater, chip notching, primary and secondary grooving. This paper discusses the wear behavior of carbide tool utilizing response surface methodology. Machining tests were carried out by using EN-31 steel with tungsten carbide tools using soluble oil-water mixture lubricant under different machining variables. The study reveals that tool wear is mainly affected by cutting speed ,feed rate and tool nose radius whereas, depth of cut have negligible effect. However, response surface methodology combined with factorial design of experiments is a better alternative to the traditional one-variable- at –a-time approach for studying the effects of cutting variables on responses such as tool wear.

Keywords: Tool wear rate, Factorial design, Response surface methodology