Authors: Milton Sergio Fernandes De Lima, Fabricio Prieto Ladario, Davi Neves, Anselmo Eduardo Diniz
Addresses: Instituto de Estudos Avancados (IEAv), Sao Jose dos Campos (SP), 12228-001, Brazil. ' Instituto Tecnologico de Aeronautica (ITA), Sao Jose dos Campos (SP), 12228-900, Brazil. ' Instituto de Estudos Avancados (IEAv), Sao Jose dos Campos (SP), 12228-001, Brazil. ' Faculdade de Engenharia Mecanica, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), 13083-860, Brazil
Abstract: Surface modification of high-speed steel drills using laser has been proposed as a step before physical vapour deposition in order to increase the adhesion of the titanium nitride coating on the tool substrate. A copper vapour laser and a scanning-head system were used to produce highly controlled laser ablation on the surface. In the current work, the laser average power varied from 0.5 to 6 W and the laser shots were applied next to one another. After laser surface modification and coating, the drills were used to machine low-alloy carbon steel and stainless steel in a CNC machine. The tool lives were then compared to those obtained with the same kind of tool but whose substrate was prepared conventionally. The laser-treated drills had a longer lifetime than conventional ones. Under the conditions of this study, the laser-treated drills presented a 40% higher performance than conventional drills for carbon steel machining. The increase in performance reached 400% in stainless steel drilling. In general, laser processing with an average power of 1 W yielded the best results.
Keywords: laser surface treatment; laser surface texturing; CNC machining; surface modification; drilling; microtexturing; non-conventional processes; steel machining; microstructure; high speed steel; HSS drills; adhesion; titanium nitride coating; tool substrate; copper vapour lasers; scanning-head systems; laser ablation; carbon steel; stainless steel; tool life.
International Journal of Surface Science and Engineering, 2011 Vol.5 No.2/3, pp.98 - 115
Available online: 21 Jul 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article