1983 年 54 巻 3 号 p. 149-154
The properties of 18Ni-8Co-4Mo maraging steel compacts using maraging steel powders containing 13% and 18%Ni were investigated and the engine test was performed.
The results are summarized as follows:
1) The maraging steel compacts using 13Ni-8Co-4Mo powder were found to have higher strength and hardness than normal.
2) As the sizing operation is performed before aging, the sintered maraging piston ring keeps its shape proper even without machining.
3) From the analysis through heat-soak-back test of turbo-charged engine, it was observed that the existence of carbonized oil film on surface of piston ring can prevent it from elevation of temperature and direct metal contact.
4) Only piston ring without machining is able to reduce the friction and the wear under ultra-high speed operation in exhaustion gas.