| 摘要 |
PROBLEM TO BE SOLVED: To give electric conductivity to a ceramic article without deteriorating mechanical toughness and frictional characteristics and to enable an inexpensive elector-discharge machining by mixing a tetragonal zirconia alloy or a zirconia- alumina composite with zirconium diboride, crushing and compressing the resultant mixture and carrying out sintering in an atmosphere of Ar. SOLUTION: Granular zirconia having >=99.9% purity is mixed with a 2nd oxide selected from among 0.5-5mol% Y2 O3 , 0.1-1.0mol% MgO, 0.5-15mol% CeO2 , 0.5-7.0mol% Sc2 O3 and 0.5-5mol% CaO and the resultant mixture is heated to <=200 deg.C under 100MPa pressure to obtain a tetragonal zirconia alloy. This zirconia alloy or a zirconia-alumina composite is mixed with zirconium diboride to obtain a granular mixture. This mixture is compressed under 10,000-30,000psi pressure for 60-100sec and sintered by heating at 1,300-1,700 deg.C under 69-207MPa pressure for 1-3hr in an atmosphere of Ar. |
