• Corrosion Science and Technology
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• 제9권6호
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• pp.331-337
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• 2010

This study compared the macro and micro electrochemical characteristics at the local area of welding metal on dissimilar welding parts for type 304 stainless steel (SS) and type 316L SS. The materials are used for double wall gas pipe of duel fuel engine for a ship. The various potentiodynamic experiments were performed several times in 10% ${H_2C_2O_2}{\cdot}{H_2O}$ solution using macro and micro methods, respectively. The micro electrochemical experiments conducted to resolve at local area on cross-section of dissimilar welding materials by micro-droplet cell device. The micro-droplet cell techniques can be used almost electrochemical experiments to resolve corrosion characteristics of the limited electrode area of the metallic surface between wetted spot of working electrode and tip of sharpened capillary tube. The results of macro electrochemical experiments show that resistance of active dissolution reaction at welding zone was high due to low current density by formation of passivation protection film at passive region. According to the micro electrochemical experiment, the corrosion current density of welding zone and bond zone were relatively high.

• Journal of Advanced Marine Engineering and Technology
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• 제35권1호
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• pp.68-74
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• 2011

본 논문은 LNG 선박의 이중연료엔진의 이중벽 가스파이프의 재료인 STS 304와 STS 316L에 대하여 GTAW에 의해 용접된 동종 및 이종 용접부의 기계적 특성과 용접성을 평가하였다. STS 304 동종 용접부의 경우, STS 316L 동종 용접부에 비해 모재 대비 현저하게 기계적 특성이 감소하는 경향을 나타냈다. 미세조직 관찰 결과, STS 304 동종 용접부가 STS 316L 동종 용접부에 비해 침상 페라이트가 많이 형성되어 상대적으로 높은 경도를 나타냈다.