| 摘要 |
PROBLEM TO BE SOLVED: To provide a low-cost iron-based sintered body capable of exerting excellent toughness, or an impact resistance value, and sufficient strength. ! SOLUTION: An iron-based sintered body is formed by pressure-molding a mixed powder prepared by mixing together a raw material iron powder comprising one or more of pure iron powder and metal alloy powders, graphite powder and an arbitrarily blended modification powder and sintering the resultant molding. The sintered body contains no Cu and Ni and has a sintered body density ratio (ρ'/ρ0'×100%), or a ratio of the bulk density (ρ') to the theoretical density (ρ0'), of 85-95% and an average maximum pore length of residual pores of 120 μm or smaller. The maximum pore length of residual pores can be controlled by appropriate particle size control of the raw material iron powder. Owing to the control of the residual pores or the particle size control of the raw material iron powder, the iron-based sintered body is low-cost and exerts quite |
