Budget Amount *help |
¥18,070,000 (Direct Cost: ¥13,900,000、Indirect Cost: ¥4,170,000)
Fiscal Year 2014: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
Fiscal Year 2013: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
Fiscal Year 2012: ¥12,740,000 (Direct Cost: ¥9,800,000、Indirect Cost: ¥2,940,000)
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Outline of Final Research Achievements |
Stress Corrosion Cracking (SCC) was studied using 3D characterization methods for a weld component made of Inconel and low alloy steel (LAS) and an austenitic stainless steel. Macro- to micro-scopic residual stress measurements and creviced bent beam SCC tests were performed for Inconel/LAS samples. The possible reasons for the suppression of SCC crack propagation near the weld interface found at a nuclear power plant were estimated to include the crack branching at the grain boundary (GB) parallel to the interface, i.e., Type II GB, compressive residual stresses in the LAS region and crack tip oxidation in the LAS at the interface. SCC crack propagation behavior in CT specimens of sensitized SUS304 steel was observed three-dimensionally using a serial sectioning technique. Crack branching and stress/plastic strain distribution were influenced by stress intensity factor, corrosion environment and microstructure particularly character of grain boundary and delta ferrite grains.
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