Development of Corrosion Fatigue Testing System in Marine Environment for WELded Structural Components and Establishment of Design Standard for Corrosion Fatigue

Research Project

Project/Area Number	61850134
Research Category	Grant-in-Aid for Developmental Scientific Research
Allocation Type	Single-year Grants
Research Field	溶接工学
Research Institution	The University of Tokushima,Faculty of Engineering
Principal Investigator	AKIZONO Kocihi The University of Tokushima,Faculty of Engineering, 工学部, 教授 (90035577)
Co-Investigator(Kenkyū-buntansha)	池田猛 (株)日進機械, 技術部, 部長田中輝彦 (株)鷺宮製作所, 副工場長上田和男徳島県商工労働部(前徳島県工業試験場), 課長補佐 MURAKAMI Ri-ichi The University of Tokushima, Faculty of Engineering, 工学部, 助教授 (00112235) TANAKA Teruhiko Saginomiya Co.Ltd. IKEDA Takeshi Nisshin Machine Co.Ltd. UEDA Kazuo Tokushima Prefectural Industtial Research Institute 越塚篤男 (株)鷺宮製作所, 工場長
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥18,800,000 (Direct Cost: ¥18,800,000) Fiscal Year 1987: ¥4,500,000 (Direct Cost: ¥4,500,000) Fiscal Year 1986: ¥14,300,000 (Direct Cost: ¥14,300,000)
Keywords	Elded joint / fractography / DC potential drop mesurement method / residual stress corrosion fatigue / computor control system / 海洋環境 / 疲労試験機 / 60キロ級商張力鋼 / 金属材料
Research Abstract	In the present study, a corrosion fatigue crack propagation testing under tghe marine environment was carried out for butt welded joints of HT60 steel in order to establish the design standard for corrosion fa- tigue. The fatigue crack propagation rate of base metal in air showed scarecely the depandence on stress ratio. Hile the corrosion fatigue crack propagation rate in marine environment depended remarkably on the stress ratio. The corrosion fatigue crak propagation rate was smaller for welded joint than for base metal, and decreased with decreasing the stress ratio. Such crrosion fatigue behavior resulted from the welding residual stress and the wedging effect bu calcareous deposits.