Análise da qualidade superficial no fresamento de aço P20 com diferentes tratamentos de ferramentas e condições de lubrirrefrigerantes

Abstract

This work studied the effect of edge preparation and its interaction with minimum quantity of lubricant (MQL) application over the surface integrity of the workpiece and wear in milling. The necessity of high productivity of the industry allied with high efficiency that they need drives technological advances in the machining area. Edge preparation processes come to attend those needs, increasing the durability and reliability of the tools. Moreover, the necessity for economy in metalworking fluids, without losing in performance impels the use of alternatives such as MQL. Both the edge preparation and the use of MQL in machining end up impacting the process. These have connection with changes in surface quality and wear, as well as on economic aspects of the process. In regarding of this, experimental tests were conducted by using tools treated with drag finishing and polishing with abrasive brushes. The experiments also evaluated the use of MQL with and without extreme pressure additives. The tests consisted in generating surfaces, picturing different stages of the tools life. Roughness analysis, texture and dimensional measurements of the tools were performed after treatment. Texture and roughness on the workpiece were analyzed at different stages of the tool life. Finally, microhardness and plastic deformation were measured on the workpiece for an intermediate stage of tool life. The results show that the treatments result in different characteristics on the tool. Both treatments as the application of MQL have significant effect on the texture, roughness and affected layer as well as on the wear. The tools that went trough polishing presented good stability when used with MQL, reaching a machining length up to 20% higher in comparison with the original tools in dry milling.