Influência do método lubrirrefrigerante sobre a usinabilidade do aço inoxidável supermartensítico

• Ano de defesa: 2021
• Autor(a) principal: Fernando Júnio Duarte
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; ENG - DEPARTAMENTO DE ENGENHARIA MECÂNICA; Programa de Pós-Graduação em Engenharia Mecanica; UFMG
• Palavras-chave em Português: Aço inoxidável supermartensítico; Torneamento; Temperatura e força de usinagem; Acabamento superficial; Vida e desgaste de ferramenta; Engenharia mecânica; Aço inoxidável; Usinagem
• Link de acesso: http://hdl.handle.net/1843/39308; https://orcid.org/0000-0001-8934-7606

In this study, the influence of cutting speed, feed rate, and lubrication-cooling method (dry cutting, flooding, and vortex tube air cooling) on tool temperature, machining force, surface roughness, wear mechanisms and tool life was investigated during turning of supermartensitic stainless steel using tungsten carbide tools. The results showed that the variation in the heating rate affects the phase transformation temperatures of the work material and, therefore, it is suggested that the application of cutting fluids can influence its thermodynamic state during turning. In addition, tool temperature was influenced by the lubrication/cooling method and cutting parameters (cutting speed and feed rate). On the other hand, the lubrication-cooling method did not significantly affect the components of the machining force and the machined surface roughness. Machining force components were mainly influenced by feed rate, followed by cutting speed and the interaction between feed rate and cutting speed. The surface roughness of the workpiece was influenced by feed rate, which increase was responsible for a deleterious effect on surface quality. Furthermore, tool life tests using cutting speeds of 160 m/min and 200 m/min with feed rate of 0.1 mm/rev indicated that the wear mechanisms are sensitive not only to a variation in cutting speed but also to the lubrication-cooling method. The wear mechanisms presented in the cutting tools are not the result of one single mechanism, but a combination of abrasion, attrition (adherence and drag) and diffusion.