公开(公告)号：US5804523A

公开(公告)日：1998-09-08

申请号：US853410

申请日：1997-05-09

申请人： Takehiro Oda ,  Koichi Tanaka ,  Tomohiro Iwaida ,  Sentaro Yamamoto ,  Shoji Kohsaka ,  Masahiro Sato ,  Hideki Uchimura ,  Kenichi Tajima

发明人： Takehiro Oda ,  Koichi Tanaka ,  Tomohiro Iwaida ,  Sentaro Yamamoto ,  Shoji Kohsaka ,  Masahiro Sato ,  Hideki Uchimura ,  Kenichi Tajima

IPC分类号： C04B35/593 ,  C04B35/587

CPC分类号： C04B35/593 ,  C04B35/5935

摘要： A sintered product of silicon nitride containing not smaller than 70 mol % of a .beta.-silicon nitride as well as an element of the Group 3a at least including Lu of periodic table and impurity oxygen, wherein when the content of the element of the Group 3a of periodic table and the content of the impurity oxygen are, respectively, expressed being reckoned as the amount of an oxide of the element of the Group 3a of periodic table (RE.sub.2 O.sub.3) and as the amount of SiO.sub.2 of impurity oxygen, their total amount is from 2 to 30 mol %, the molar ratio (SiO.sub.2 /RE.sub.2 O.sub.3) of the amount of the element of the Group 3a of periodic table reckoned as the oxide (RE.sub.2 O.sub.3) thereof to the amount of impurity oxygen reckoned as SiO.sub.2 is from 1.6 to 10, and the intergranular phase of the sintered product chiefly comprises a crystal phase consisting of the element of the Group 3a of periodic table, silicon and oxygen and a process for producing the same. The sintered product has a large strength from room temperature through up to high temperatures and maintains excellent resistance against oxidation even at high temperatures, and exhibits excellent resistance against creeping and excellent breaking toughness.

摘要翻译： 包含不小于70mol％的β-氮化硅的氮化硅的烧结产品以及至少包括Lu的元素周期表和杂质氧的第3a族的元素，其中当第3a族元素的含量 的周期表和杂质氧的含量分别表示为元素周期表（RE 2 O 3）的第3a族元素的氧化物的量和杂质氧的SiO 2的量，它们的总量是 2〜30摩尔％时，作为氧化物（RE 2 O 3）的元素周期表中的元素的量与作为SiO 2计算的杂质氧的量的摩尔比（SiO 2 / RE 2 O 3）为1.6〜10 ，并且烧结体的晶间相主要包含由元素周期表第3a族元素，硅和氧组成的结晶相及其制造方法。 该烧结体从室温至高温具有很大的强度，即使在高温下也能保持优异的抗氧化性，并且具有优异的抗蠕变性和优异的断裂韧性。