Investigating the effects of cutting parameters on the hole quality in drilling the Ti-6Al-4V alloy: Preiskava vpliva parametrov rezanja na kvaliteto izvrtine, izvrtane v zlitino Ti-6Al-4V

In this study, the effects of cutting parameters on the surface roughness, burr height, hole-diameter deviation, cutting temperature and structure of a chip formation were investigated during the drilling of the Ti-6Al-4V alloy. For this purpose, the Ti-6Al-4V alloy was drilled at different cutting parameters, longitudinally in the 10 mm depth with Ř = 10 mm high-speed-steel (HSS) drills, having 90°, 118°, 130° and 140° point angles on the CNC vertical machining centre. Experiments were carried out at the (12.5, 18.75 and 25) m/min cutting speeds and the (0.05, 0.1 and 0.15) mm/r feed rates without using the cutting fluid. As a result, as the feed rate and the drill-point angle were increased, the surface roughness increased as well; however, as the cutting speed increased, the surface roughness decreased. When the feed rate and drill-point angle increased, the burr height decreased. On the other hand, an increase in the cutting speed increased the burr height. In general, an increase in the feed rate and drill-point angle increased the hole diameters, and the hole diameters obtained were close to the nominal size when the cutting speed was increased. V tej študiji so bili preiskovani vplivi parametrov rezanja na hrapavost površine, višino zarobka, odmike premera izvrtine, temperaturo rezanja in strukturo nastalega izvrtka pri vrtanju zlitine Ti-6Al-4V. V ta namen je bila zlitina Ti-6Al-4V vrtana na vertikalnem CNC obdelovalnem stroju pri različnih parametrih rezanja vzdolžno v globino 10 mm s svedri iz hitroreznega jekla (HSS) premera 10 mm, ki so imeli vršni kot 90°, 118°, 130° in 140°. Preizkusi so bili izvršeni pri hitrostih rezanja (12,5, 18,75 in 25) m/min in podajanju (0,05, 0,1 in 0,15) mm/r, brez uporabe hladilne tekočine. Rezultati so pokazali, da pri povečevanju podajanja in večanju vršnega kota svedra narašča tudi hrapavost površine, vendar pa se pri povečevanju hitrosti rezanja zmanjšuje hrapavost površine. Če se povečujeta podajanje in velikost vršnega kota, se zmanjšuje višina zarobka. Po drugi strani povečanje hitrosti rezanja poveča višino zarobka. Na splošno velja, da povečanje podajanja in povečanje vršnega kota svedra povečujeta premer izvrtine. Premeri izvrtin so bili blizu nazivni velikosti, če se je povečala hitrost rezanja.