Monitoramento das forças e desgaste da ferramenta durante o fresamento concordante e discordante do aço ABNT-4140

Abstract

The machining operation by milling is widely used in the mechanical processing industries for its ability to machine parts of the most diverse profiles and ensuring good productivity when it comes to the removal of material. However, the milling operation can occur in two ways with respect to the cutting direction, one in the down-milling and up-milling cutting direction. The correct programming of this sense of cut for each specific process becomes very relevant when it comes to obtaining good results. This process influence on the final result as average roughness, temperature, tool wear and consequently on the cost of production. On this purpose, this study of the down-milling and up-milling cutting direction during milling of ABNT 4140 steel. Thus, high speed steel milling was used, with 6 mm diameter. The per tooth was varied, the cutting speed and cutting depth were maintained constant during the test. Three characteristics were evaluated: average surface roughness, cutting force and tool wear. In relation the average roughness, higher values were found to parameters of the Fz 0,018 mm in moviment down-milling. Higher values of average roughness were found to parameters of the Fz 0,03 and 0,04 mm in moviment up-milling. The cutting force were higher due to tool wear. Higher cutting force were found in the moviment down-milling and feed per tooth of 0,018mm. The results showed that the wear of the tool was more severe for the smaller feed and when using the down-milling direction. The wear by abrasion, plastic deformation and adhesion in the tools was identified, being the wear by abrasion more evident in the down-milling moviment. Plastic deformation in the up-milling moviment and a possible adhesion were found in both moviments.