マグネシウム合金鋳物MC2の旋削被削性に及ぼす工具横切れ刃角の影響

抄録

Turning machinability tests were performed on the magnesium alloy castings MC2 by measuring cutting resistance, cutting ratio, surface roughness, cutting temperature and chip forming. Regardless of side cutting edge angle, cutting resistance of the alloy was independent of cutting speed, and was affected remarkablly by increasing feed angle. The traversing force decreased with increasing side cutting edge angle. Both cutting ratio and shear angle increased with acceleration of cutting speed and feed. The machined surface finishing showed inferior with increasing side cutting edge angle and feed. The surface roughness with side cutting edge angle 0° was superior or nearly to that calculated theoretically on the basis of feed marks, but the surface roughness with side cutting edge angle 5 to 15° showed higher value. The cutting temperature increased with increasing cutting speed and/or feed. The rising rates of cutting temperature decreased with increase of cutting speed. The highest cutting temperature was 803K. But there was no trouble in flaming during cutting. Both large and small spiral coil type chips were easily treatable.