Title:
METHOD OF COMPREHENSIVELY EVALUATING CREEP LIFE EXPECTANCY OR LIFE SPAN
Document Type and Number:
WIPO Patent Application WO/2005/124315
Kind Code:
A1
Abstract:
A method of accurately evaluating the life expectancy or the life span of a creep-damaged device member irrespective of whether the grained part is fine grained or coarse grained. The life expectancy or the life span is represented by the time until the creep-damaged device member creep-ruptures. The number of linked voids present over a half or more of each length of two or more grain boundaries in areas of up to 1 mm2 of the surface of the device member is determined. The ratio of the number of the specific linked voids to the area of 1 mm2 is used as L parameter. As the void grain boundary occupancy ratio, the ratio of the total of the lengths of all the voids present at the grain boundaries in the surface of the device member to the length of one grain boundary within the area of 1 mm2 is determined for each grain boundary, and the maximum value is used as M parameter The life expectancies or life spans of the device member based on the L and M parameters are evaluated, and the shorter one is determined as the life expectancy or life span of the device member.
Inventors:
NISHIDA HIDETAKA (JP)
Application Number:
PCT/JP2005/011268
Publication Date:
December 29, 2005
Filing Date:
June 20, 2005
Export Citation:
Assignee:
CHUGOKU ELECTRIC POWER (JP)
NISHIDA HIDETAKA (JP)
NISHIDA HIDETAKA (JP)
International Classes:
G01M99/00; G01N3/32; G01N17/00; G01N33/20; G01N3/00; (IPC1-7): G01N17/00; G01M19/00; G01N3/32; G01N33/20
Domestic Patent References:
| WO2002014835A1 | 2002-02-21 |
Foreign References:
| JPH11230928A | 1999-08-27 |
Other References:
KIKUCHI K. ET AL: "Grain Boundary Damage for Pre-strained material", NIPPON KIKAI GAKKAI TSUJO SOKAI KOENKAI KOEN RONBUNSHU, vol. 73, no. 2, 1 April 1996 (1996-04-01), pages 274 - 275, XP002995865
KIKUCHI K. ET AL: "A Proposal of Grain Boundary Damage Parameter", JOURNAL OF THE SOCIETY OF MATERIALS SCIENCE JAPAN, vol. 44, no. 505, 15 October 1995 (1995-10-15), pages 1244 - 1248, XP002995866
NISHIDA H.: "The Development of New Residual Life Assessment Method at the High Temperature Steam Piping Welding Joints", NIPPON KIKAI GAKKAI ZAIRYO RIKIGAKU BUMON KOENKAI KOEN RONBUNSHU, 4 September 2004 (2004-09-04), pages 121 - 122, XP002995867
KIKUCHI K. ET AL: "A Proposal of Grain Boundary Damage Parameter", JOURNAL OF THE SOCIETY OF MATERIALS SCIENCE JAPAN, vol. 44, no. 505, 15 October 1995 (1995-10-15), pages 1244 - 1248, XP002995866
NISHIDA H.: "The Development of New Residual Life Assessment Method at the High Temperature Steam Piping Welding Joints", NIPPON KIKAI GAKKAI ZAIRYO RIKIGAKU BUMON KOENKAI KOEN RONBUNSHU, 4 September 2004 (2004-09-04), pages 121 - 122, XP002995867
Attorney, Agent or Firm:
Hori, Susumu (1-1 Yoyogi 2-chom, Shibuya-ku Tokyo, JP)
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