公开(公告)号：JP2002068843A

公开(公告)日：2002-03-08

申请号：JP2000258568

申请日：2000-08-29

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： HIROSAKI NAOTO ,  NISHIMURA SATOYUKI ,  YAMAMOTO YOSHINOBU ,  MITOMO MAMORU

IPC: C04B35/584

Abstract: PROBLEM TO BE SOLVED: To provide a silicon nitride sintered compact having both of high strength and superior antioxidation property at high temperature. SOLUTION: In the sintered compact, the intergranular phase consists of a substantially single phase of Lu4Si2O7N2 crystal phase. The composition of the sintered compact represented in the Si3N4-SiO2-Lu2O3 ternary constitution diagram corresponds to the boundary or inside of triangle ABC having three points of point A: Si3N4, point B: 28 mol% SiO2-72 mol% Lu2O3 and point C: 16 mol% SiO2-84 mol% Lu2O3 as vertexes.

公开(公告)号：JP2003121320A

公开(公告)日：2003-04-23

申请号：JP2001311065

申请日：2001-10-09

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： YAMAMOTO YOSHINOBU ,  MITARAI YOKO ,  HIROSAKI NAOTO ,  HARADA KOJI

IPC: G01N1/28

Abstract: PROBLEM TO BE SOLVED: To provide a method for accurately and simply analyzing an iridium alloy, enabling the melting and chemical analysis of the iridium alloy chemically stable and difficult to melt because of a metal bond. SOLUTION: An alkaline peroxide is added to a powder sample of the iridium alloy to heat and melt the iridium alloy. This molten iridium alloy is dissolved in aqua regia to obtain a solution sample which is, in turn, used to quantify the element in the iridium alloy.

公开(公告)号：JP2002137968A

公开(公告)日：2002-05-14

申请号：JP2000324327

申请日：2000-10-24

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： HIROSAKI NAOTO ,  NISHIMURA SATOYUKI ,  YAMAMOTO YOSHINOBU ,  MITOMO MAMORU

IPC: C04B35/584

Abstract: PROBLEM TO BE SOLVED: To provide a material excellent in creep-resistant property by crystallizing assistant having a high fusing point on grain boundary efficiently, with only an ordinary sintering process dispensing with specific heat treatment. SOLUTION: The silicon nitride sintered compact is characterized in that the sintered compact composed of a grain boundary phase of silicon nitride grain and acid nitride grain, the composition of which is shown on the ternary system constitutional diagram of Si3N4-SiO2-Lu2O3, in a triangle constituted of three points, a point A: Si3N4, a point B: 40 mol% SiO2-60 mol%-Lu2O3, a point C: 60 mol% SiO2-40 mol%-Lu2O3.