| 摘要 |
PROBLEM TO BE SOLVED: To provide both an engine part having a low thermal conductivity and a high strength at high temperatures and a method for producing the engine part. SOLUTION: This engine part is formed from ceramics obtained by sintering a molded product prepared by compounding 80-95.5 wt.% of a cordierite powder having <=5 μm average particle diameter, 0.5-20 wt.% of a rare earth element oxide having <=2 μm average particle diameter and further <=30 wt.% of at least one kind selected from silicon nitride, silicon carbide and silicon oxynitride at a temperature within the range of 1,200-1,500 deg.C and then cooling the sintered molded product to 1,000 deg.C at <=10 deg.C/min rate. The ceramics contain cordierite crystal grains having <=10 μm average grain diameter, have <=5% porosity of open pores, further contain a compound oxide crystal phase of the rare earth element oxide and silicon oxide deposited on the grain boundary of cordierite crystal grains and have <=5 W/m.K thermal conductivity at ambient temperature and >=80 MPa strength at 800 deg.C. |
