HOLES GEOMETRY ASSESSMENT MACHINED IN A LEAGUE Al-Si USING STEEL DRILL FAST AND HARD METAL VK5 WITH HIGH SPEED CUTTING
Paulo Sérgio Martins1; José Rubens Carneiro2; Pedro Brito2; Gilmar Cordeiro2; Leonardo Dutra1; André Bragança Carvalho França2
1 Fiat FCA; 2 Puc Minas
doi:10.20906/CPS/COB-2015-0787
Resumo
With the development of new cutting tool technologies as the geometry and materials, cutting speeds used today reach values AL-Si inconceivable for two decades. In the automotive industry, steel and cast iron have been gradually replaced by less dense materials, better machinability and money. Al-Si alloys, in this context, have gained use in space and heads, gear boxes, among others. Holes are present in various diameters and depths and need to be machined in the shortest time possible within narrow dimensional tolerance ranges, shape (roundness, taper, roundness, etc.) and roughness. This study evaluated the drilling of an Al-Si Die-cast alloy using high speed steel drill VK5 in cutting speed of 340m / min, 380m / min and 430m / min from the point of view of tolerance of the product and tool wear. In this study, we used optical microscopy and scanning electron with EDS analyzer to monitor the wear process. The measurement of geometrical parameters and the surface texture was made in Talyrond 4 Coord equipment A and Her 3 Ivy coordinate and Taylor Hobson profilometer Form Talysurf Series-roughness with a Gaussian filter of 50% cut-off 0.8 mm, and a length of 4, 8mm. Thus we analyses the form surface roughness parameters Ra, Rz and Rt in both processes and compared them with each other. In both cases remained constant rotation in 8.000rpm, forward speed (vf) in 2880mm / min cutting speed (vc) in 340m / min, 380m/min and 430m/min. Comparing the evolution of the surface Ra, Rz and Rt, it is noted that the same remained stable over the testing
Palavras-chave: Holes; surface parameters; drilling, cutting Drill VK5; High speeds; geometric parameters; alloy Al-Si