Authors: Faraz Akbar; Paul Mativenga; Mohammad Sheikh
Addresses: Department of Automotive and Marine Engineering, NED University of Engineering and Technology, University Road, Karachi – 75270, Pakistan ' School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, P.O. Box 88, Manchester, M60 1QD, UK ' School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, P.O. Box 88, Manchester, M60 1QD, UK
Abstract: In this paper, a methodology is presented to reduce the heat flux into the tool for multilayer physical vapour deposition coatings. It takes into account the thickness values of the coatings, the contact phenomena, and the thermal properties of the tool and the workpiece materials. This leads to a heat partition based design of coatings in which the heat partition from the interface to the film surface is decreased by optimising the other coating parameters. Cutting tests were conducted on AISI/SAE 4140 high-strength alloy steel using multilayer TiAlN/TiN coated tool. Cutting temperatures were measured experimentally using an infrared thermal imaging camera. The sticking and sliding regions were established using scanning electron microscopy and energy-dispersive X-ray analysis. A multilayer TiAlN/TiN coating was designed for enhanced reduction of the heat flux that goes into the tool. The approach sets a view that could be developed for a generic optimisation of coating layout.
Keywords: heat partition; multilayer coated tools; metal cutting; finite element method; FEM; high speed machining; HSM; infrared thermal imaging camera; cutting tool coatings; thermal properties; tool-chip contact area; sticking region; sliding region; tool wear; heat flux; physical vapour deposition; PVD coatings; alloy steel; coating design; optimisation; coating layout.
International Journal of Machining and Machinability of Materials, 2013 Vol.14 No.4, pp.363 - 386
Received: 25 Jul 2012
Accepted: 09 Apr 2013
Published online: 26 Dec 2013 *