Title: A case-study on the mechanism of flank wear during laser-assisted machining of a titanium alloy
Authors: R.A. Rahman Rashid; Suresh Palanisamy; Shoujin Sun; M.S. Dargusch
Addresses: School of Engineering, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Victoria 3122, Australia; Defence Materials Technology Centre, Victoria 3122, Australia ' School of Engineering, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Victoria 3122, Australia; Defence Materials Technology Centre, Victoria 3122, Australia ' School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Victoria 3083, Australia ' Queensland Centre for Advanced Materials Processing and Manufacturing (AMPAM), School of Mechanical and Mining Engineering, The University of Queensland, Queensland 4072, Australia; Defence Materials Technology Centre, Victoria 3122, Australia
Abstract: In recent years, researchers have been investigating various technologies including laser-assisted machining (LAM) to improve the machinability of titanium alloys which is considered to be one of the difficult-to-cut materials. The LAM process involves heating the titanium workpiece with a laser beam of sufficient power to soften the material before it engages with the cutting tool. Benefits of LAM include significant reduction in cutting forces as well as better surface finish. However, as diffusion wear is the most dominant tool wear mechanism associated when machining titanium alloys, the effect of the additional heat from laser preheating on the cutting tool life is not clearly understood. Therefore, this paper aims at investigating the tool life of an uncoated carbide tool during LAM of Ti-6Al-4V alloy, as well as identifying the principal flank wear mechanisms involved during the cutting process. It was found that the tool life was reduced by about 8% when machining the workpiece with laser preheating. Moreover, it was found that the carbon from the cutting tool diffused into the titanium built-up edge formed in the vicinity of the cutting zone from where it was carried out through the chips. This considerably weakened the cutting edge of the tool resulting in accelerated tool wear.
Keywords: titanium; Ti-6Al-4V; laser-assisted machining; LAM; cutting forces; tool life; tool wear; diffusion wear; flank wear.
International Journal of Machining and Machinability of Materials, 2017 Vol.19 No.6, pp.538 - 553
Received: 20 May 2016
Accepted: 15 Oct 2016
Published online: 02 Jan 2018 *