公开(公告)号：JP2006348385A

公开(公告)日：2006-12-28

申请号：JP2006177981

申请日：2006-06-28

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： YAMADA KATSUMI ,  OKADA KOICHI ,  MUNEKI MASAICHI ,  ABE FUJIO

IPC: C22C38/00 ,  C22C38/54

Abstract: PROBLEM TO BE SOLVED: To provide an MX carbonitride precipitation-strengthened heat-resistant steel which is a heat-resistant steel utilizing a strengthening mechanism by the precipitation of carbonitride and in which the high-temperature creep strength at 600 to 650°C is improved. SOLUTION: The MX carbonitride precipitation-strengthened heat-resistant steel utilizes a strengthening mechanism by the precipitation of MX carbonitride and has the improved high-temperature creep strength at 600 to 650°C, wherein the content of a compound MX carbonitride comprising NbC (TaC) and VN is restricted to below 30% by weight with respect to the entire precipitated MX carbonitride. COPYRIGHT: (C)2007,JPO&INPIT

公开(公告)号：JP2003253397A

公开(公告)日：2003-09-10

申请号：JP2002104524

申请日：2002-02-28

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： YAMADA KATSUMI ,  MUNEKI MASAICHI ,  OKADA KOICHI ,  IGARASHI MASAAKI ,  ABE FUJIO

IPC: F01D5/28 ,  C22C38/00 ,  C22C38/30

Abstract: PROBLEM TO BE SOLVED: To improve a high-temperature creep property in a temperature range of 650°C or higher of a martensitic heat-resistant steel, enable the higher high- temperature creep property to be kept for a long time, make the thermal expansion characteristics in the temperature range of 650°C or higher to be low, and improve the thermal fatigue characteristics. SOLUTION: In the martensitic heat-resistant steel having a martensite single- phase structure at room temperature, in which carbides do not precipitate, a structure in the temperature range of 650°C or higher has two-phases comprising an austenitic phase of a parent phase and a finely dispersed and precipitated intermetallic compound phase, or three phases comprising the austenitic phase of the parent phase, a ferritic phase and the finely dispersed and precipitated intermetallic compound phase. COPYRIGHT: (C)2003,JPO

公开(公告)号：JP2003089802A

公开(公告)日：2003-03-28

申请号：JP2001282619

申请日：2001-09-18

Applicant: NAT INST FOR MATERIALS SCIENCE

Inventor： WANIKAWA SHUJI ,  OTAGUCHI MINORU ,  OKADA KOICHI ,  MURAMATSU YUJI

IPC: B22F1/00

Abstract: PROBLEM TO BE SOLVED: To provide a method for manufacturing mechanically alloyed powder in which oxidation and the amount of incorporated gas both causing deterioration in the mechanical properties of the resultant compact are decreased for the purpose of avoiding decrease in density due to the presence of inert gas in a ball mill as a manufacturing vessel under severe conditions and also to provide a method for easily removing the incorporated gas. SOLUTION: When manufacturing the mechanically alloyed powder by mechanical alloying using the manufacturing vessel, the atmosphere within the manufacturing vessel in an agitation and grinding step is made to vacuum or gaseous hydrogen and gaseous nitrogen. Reduction heat treatment can also be added.