2002 年 49 巻 5 号 p. 438-443
The authors have previously reported on the warm compacted and normal temperature (1140°C) sintered P/M sprockets of the roller chain system of non-DIG (normal MPI gasoline) engines. In this new development, the mechanical properties of several warm-compacted and high-temperature sintered P/M steels were investigated. A wear test was also conducted to examine the anti-wear characteristics of these material using dummy engines. Finally, sprockets of silent chain system of DIG engines were developed that can endure sever wear conditions. The base powder used was a hybrid material (Distaloy DC1). It was 2mass% Ni (nickel) and was diffusion bonded to pre-alloy Fe-1.5mass%Mo (molybdenum) powder. The warm compaction was conducted with the powder, die and tools at 130°C. The sintering temperature was 1190°C and heat treatment was also applied to the sprockets.