Desempenho de óleos vegetais comestíveis aplicados por MQF no fresamento frontal do aço ABNT 1045

Abstract

Searching for a more environmental friendly and at the same time technically viable machining, this work investigates the application of edible refined vegetable oils (cotton, babaçu, canola, sunflower, corn and soybeans) as cutting fluids using by the Minimum Quantity of Fluid (MQF) technique on the machinability of ABNT 1045 steel, in face milling with carbide tools. Firstly, considering the machinability parameters (machining force and power, vibration and surface finish) of the cutting fluids raised in specific tests, the results were compared with those obtained with the MQF application of commercial industrial oil with the flood cooling application of a mineral base soluble oil and dry condition. The two refined vegetable oils that presented the best performance in the previousmachinability tests (cotton and canola) were used in tool life trials and compared with the dry condition and with the MQF application of the commercial industrial oil. In these tests the wear of the tools was monitored and the wear mechanisms analyzed at the end of the tool lives within the SEM - Scanning Electron Microscope. We evaluated the life of the cutter depending on the volume of removed material (VRM), using as the criterion of end of life average flank wear (VBB = 0.35 mm) as ISO 8688-1 / 89. Among the edible vegetable oils tested best results were found for canola oil to conditions of low shear and cotton under conditions of high shear rate. Some specific tests were carried out to determine the cooling ability, the lubricant ability and the wettability of the studied oils. The cooling curves show a large heat removal capacity of the canola and cotton, and that they also had a high specific energy in the scratching test and the tests of wettability, virtually all fluids tested had a good adhesion to the surface.