Author : Samatham Madhukar 1
Date of Publication :25th May 2017
Abstract: Machinability is a property or quality of any material that can be clearly defined and quantified, to indicate how easy (or difficult) it is, to perform machining operations on it. In fact, the term is ambiguous, but the machinability of any material can be assessed using parameters like (i) tool life (ii) cutting forces (iii) power consumption (iv) surface finish and (v) chip morphology. In the current paper machinability of the materials like Mild steel, Stainless Steel and Titanium are studied; however special emphasis is given to Titanium as it difficult to machine due to high cutting forces, temperatures, chemical reactions with tools, and a relatively low modulus of elasticity. Titanium does not form a built-up edge on tools which is a common problem while machining steels and this result in good surface finishes even at low cutting speeds. The lack of a built-up edge, however, increases the alloying and abrading action of the thin chip which races over a small tool-chip contact area under high pressures. The combination of above characteristics and relatively poor thermal conductivity of titanium results in abnormally high tool-tip temperatures. To overcome this, one of the best techniques available is Cryogenic Machining. Cryogenic machining is a process in which the traditional lubro-cooling is replaced by liquid nitrogen (LN2). Liquid nitrogen is more preferable in machining to dissipate heat generated because it is cost effective, safe, non-flammable and environment friendly gas. In addition, it does not contaminate work piece and no separate mechanism for disposal is required. In the current paper, the overall machining is done on turning machine and the parameters like Cutting forces, Surface finish, Temperature at cutting area and power consumption are obtained for the three materials. The overall results are tabulated and the conclusions are drawn accordingly. The main objective of the research is to improve the machinability of materials by using Cryogenic Machining technique
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