• Proceedings of the Korean Vacuum Society Conference
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• 1993.02a
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• pp.57-58
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• 1993

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.201.2-201
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• 2002

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.292.2-292
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• 2002

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.57-57
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• 1998

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.10a
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• pp.100-100
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• 2003

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.228-229
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• 2015

생체재료로 사용되는 마그네슘 합금은 인체 내에서 매우 빠른 부식을 가지고 있고, 초기 빠른 부식으로 수소기체를 발생하여 피부나 골조직의 괴사를 일의는 문제점을 가지고 있다. 또한 부식이 진행되어 생긴 부식 산화물의 소량은 체외로 배출 되지만, 일부는 체 내에 남아 다양한 문제를 일으킨다. 이번 연구를 통해 이러한 문제점을 해결하고 생체재료로 마그네슘 합금을 안전하게 사용하기 위하여, 마그네슘 합금의 부식 거동을 확인 하고 마그네슘 표면처리 연구를 진행하였다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.143-151
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• 2021

Flexural test of reinforced concrete beam with corroded reinforcement were performed to measure the deflection, curvature and cracking moment for various bar diameter and amounts of corrosion. The amounts of corrosion are varied from 0% to 10% by weight and the bar diameters are chosen as 10mm, 13mm, and 19mm. The changes in reinforcement diameter do not affect the flexural behaviors significantly according to this experiment. If the amounts of corrosion is greater than 2%, the deflection and curvature of the beam increased and the cracking moment decreased. It means that the lower amounts of corrosion does not result structural damage in flexural member significantly as in direct tensile test. A modification factor considering an effect of amounts of corrosion is proposed based on the experiment, which can be used to determine the deflection of reinforced concrete beam with corroded reinforcement.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.4
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• pp.413-422
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• 1995

Cavitation erosion-corrosion implies damage to materials due to the shock pressure or shock wave that results when bubbles form and collapse at a metal surface within a liquid. If the liquid is corrosive to the material, a condition typically encountered in industry, the component materials may suffer serious damage by a combination of mechanical and electrochemical attack. In this study, the mild steel(SS41) was tested by using the piezoelectric vibrator with 20kHz, 24$\mu$m to cavity generation apparatus. The damage behaviour of vibration cavitation erosion-corrosion and the environment characteristics were investigated in various solutions which are seawater, tap water and distilled water. The main results obtained are as follows; 1) The cavitation erosion-corrosion damage behaviour in the seawater increases to occur at the equal degree on the middle portion and the outside portion of specimen. The distilled water specimen, on other hand, occurs beginning on the outside portion across to the middle portion of specimen. 2) The cavitation erosion-corrosion damage in the tap water of low specific resistance more increases than that in the distilled water of high specific resistance at the initial testing time and more decreases than that in it by the CaCO sub(3) film with testing time. 3) Cavitation erosion-corrosion damage characteristic divides into four regions; incubation region, acceleration region, deceleration region and steady state region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3251-3259
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• 2014

This paper presents experimental and analytical research results to predict nonlinear flexural behavior of corroded reinforced concrete beams. For this purpose, a series of test and an analytical simulation using the Maaddawy's model were carried. Test specimens of total 12 RC beams were placed in accelerated corrosion status using salt water spray test chamber for 5 months and 10 months, after they were preloaded up to 30% and 60% of the maximum load corresponding to nominal flexural strength. The test results showed that flexural strength and ductility decreased to 5.4% and 43% at the most respectively due to breakdown of bond at the steel-concrete interface. Comparative study between the analytical predictions and the experimental results showed that the Maaddawy's model can be applied to predict a real corroded RC flexural members.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.166-169
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• 2002

본 연구는 콘크리트 배합시 염분의 함량이 구조물의 부식에 미치는 영향을 조사하기 위하여 수행되었다. 콘크리트는 물 : 포틀랜트 cemente : 자갈 : 모래의 비율을 1 : 1.78 : 5.35 : 4.73의 비율로 하여 배합하였으며 염분의 함량은 0-3.5wt%의 범위에서 철근의 부식을 연구하였다. 부식특성을 연구하기 위하여 부식전위를 2년간 측정하였으며 이를 콘크리트 파괴 후의 철근의 외관 부식도와 비교하였다. 옥내와 옥외에 두었을 때 부식속도의 차이는 없었으며 염분의 함량이 증가함에 따라 활성이 큰 전위값이 측정되었다. 전위값이 낮은 시편은 부동태 피막이 파괴되어 부식이 진행하고 있었으며, 전위값이 높은 시편에서는 부식생성물이 관찰되지 않았다. 본 실험의 결과로 보강용 강재의 부식손상 정도를 자연전위 측정방법을 통하여 콘크리트내 보강용 철근의 부식거동 및 부식속도에 대한 비괴적인 전기화학적 기술로서 구조물의 손상여부를 확인할 수 있었다.