C-ring stress corrosion test for Inconel 600 and Inconel 690 sleeve joint welded by Nd:YAG laser

C-ring stress corrosion test for Inconel 600 and Inconel 690 sleeve joint welded by Nd:YAG laser were carried out to evaluate the applicability of the technique in the repair of heat exchanger tube of nuclear power plant. Corrosion test were carried out mainly in caustic solution. The applied stresses range between 207 and 414 MPa at 348 °C and the corrosion time is between 1624 and 4877 h. The experiment also has been done in primary water with one condition (379 MPa, 2931 h), and in sulphate solution with one condition (414 MPa, 1624 h). Stress corrosion cracking (SCC) was observed in the welded specimens immersed in sulphate and caustic solution but SCC was not observed in primary water. The length of SCC is related to corrosion time and applied stress. The length of SCC increases linearly with increasing corrosion time. SCC propagates as intergranular from base metal towards the weld of Inconel 690. Weld part of Inconel 690 appears to posses better resistance to SCC than base metal of Inconel 690 in caustic environment.