침입형 원소 첨가 스테인리스강 용접부 미세조직 변화 및 부식특성에 관한 연구

다국어 초록 (Multilingual Abstract)

Microstructure evolution and corrosion behavior in the simulated HAZ and real welds of high interstitial alloyed austenitic stainless steels were investigated. Three Fe-18Cr-10Mn-N-C alloys with different N and C contents were fabricated using a commercial pressurized vacuum-induction melting furnace. First, the HAZ samples with three different peak temperatures were experimentally simulated using Gleeble simulator under welding condition of 30kJ/cm heat input. In the HAZs, δ-ferrite was formed and its fraction increased with increase in the peak temperature. The electrochemical tests indicated that pitting corrosion resistance significantly decreased by the formation of δ-ferrite, however did not changed with increasing δ-ferrite fraction. Next, the samples for real welds evaluation were prepared by autogeneous welding. The corrosion behavior in real welds was good agreement with that in Gleeble-simulated HAZ. Cross sectional microstructure of real welds indicated that δ-ferrite was formed in the HAZ and thus pitting corrosion selectively occurred at δ-ferrite/austenite phase boundaries in the HAZ.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 실험 방법
• 3. 실험 결과 및 고찰
• 4. 결론
• Acknowledgement
• References

참고문헌 (Reference)

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