Efeito de diferentes condições de aplicação de fluídos lubri-refrigerantes no desgaste de brocas de aço-rápido

Abstract

Manufacturing industries are constantly searching for ways to improve the manufacturing processes and reduce costs. In machining processes, drilling is one of the most frequent operations and is one that involves severe cutting conditions. Thus, many companies still use high-speedsteel (HSS) tools to drill materials of difficult machinability, because these tools have low cost. Furthermore, the abundant application of cutting fluid is still widely practiced, despite the harmful effects that cutting fluid can cause to the environment and to the health of the machine operator. However, the world-wide trend for reduction or elimination of machining cutting fluids is also motivated by the desire to reduce total manufacturing cost. This work presents a study on the wear behavior of M2 high-speedsteel drill under different cutting fluid conditions for deephole drilling. The material used was DIN 1.2711 steel with hardness between 38 and 43 HRc. Under abundant emulsion application, the 8 mm diameter drill machined 0.64 m. Using MQL (Minimal Quantify of Lubricant), the tool machined 0.72 mm. However, with compressed air, the tool machined only 0.40 m. For all tests conditions, the abrasion marks and material adhesion were observed.

Key words: DIN 1.2711 steel, wear mechanism/type, MQL, dry cutting.