STUDIES ON THE EFFECT OF MILL MICROSTRUCTURE UPON TOOL LIFE DURING SLOT MILLING OF TI6AL4V ALLOY PARTS

Different forms of tool wear occur in the milling process. Mechanical wear, which has a range of varieties, is a typical form of wear connected with mill operating. One of the varieties of mechanical wear, frequently occurring during milling machiningresistant materials, is undesirable catastrophic wear. Avoiding that kind of wear by appropriate selection of technological parameters, sort of burning carbides and their microstructure constitutes basic information about reliability of the tool. This paper presents the findings from the experimental testing of the impact SC grain size in end mills on the cutting tool tooth (bit) service life and surface topography after slot milling Ti6Al4V alloy parts. The tool wear indicator was determined in compliance with PN-ISO 8688: 1996. It was demonstrated that ultra fine grain SC milling cutters are the most resistant to chipping, whereas the surfaces machined with these cutting tools reveals the lowest roughness. The coarse grain SC milling cutters are among those with the shortest service life of all tested tools.