浸炭・鍛造焼入れした傘歯車の特性におよぼす製造条件の影響
1992 年 78 巻 11 号 p. 1721-1728
詳細
1992 年 78 巻 11 号 p. 1721-1728
The effects of varying manufacturing process parameters on the properties of a forge quenched bevel gear after carburizing were examined.
The microstructure, height (L) to diameter (D) ratio of preform, holding time at quenching temperature and corner radius of tooth root were studied.
The following results were obtained (1) Matrix structure of tooth root of gear forged at 850 and 950°C was dual phase structure of martensite and ferrite. The fatigue properties have been correlated to this dual phase structure. (2) Suitable L/D ratio of preform was 1.0. (3) Recrystallization of austenite after forging began at 10 sec and finished at 30 sec. (4) The bending fatigue limit of the corner radius of tooth root was increased 20% by changing from 0.5 mm to 1.0 mm and was 60% higher than the conventionally processed gear.
The results of these tests have led to the development of super fatigue strength bevel gears.
