| 摘要 |
PURPOSE:To obtain the title sintered material having high toughness and reliability and capable of making electrical connection, by forming a powdery mixture of a rare-earth metal oxide, Al2O3, ZrSi2 and Si3N4 and sintering the formed article in N2 gas atmosphere under a specific condition. CONSTITUTION:Si3N4 is mixed with 0.1-10wt.% of one or more rare-earth metal oxides, 0.1-5wt.% of Al2O3, 0.1-50wt.% of ZrSi2 and, as necessary, 0.1-5wt.% of ZrN or 0.1-10wt.% of Al2O3 and the obtained mixed powder is uniaxially formed and then formed under hydrostatic pressure to obtain a formed article. The article is sintered in an N2-containing non-oxidizing atmosphere at 1600-1700 deg.C under normal pressure for >=1hr or sintered in a pressurized N2 gas atmosphere at a temperature below the decomposition temperature of Si3N4 for >=30min to obtain a sintered Si3N4 having a relative density of >=98%, a flexural strength of >=85kgf/mm<2> and a specific resistance of <=10<-1>OMEGA.cm and coated with an electrically conductive coating film of ZrN having a thickness of >=10mum. |
