• 한국주조공학회지
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• 제18권6호
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• pp.563-569
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• 1998

A Study on microstructure and elevated temperature strength of 18Cr-2Mo ferritic stainless steel castings strengthened by alloying small amounts of titanium and carbon, has been conducted. The morphology of titanium carbides showed spherical in shape and their distribution depended on the amount of alloying elements. Maximum density ($7{\times}10^5/cm^2$) of titanium carbides has been formed in the alloy containing 2.0 wt.% titanium and 0.5 wt.% carbon as alloying elements and the size of carbide particles is in the range of 0.5 to $3.0\;{\mu}m$. High temperature tensile and fatigue strength of this alloy were the highest among the alloys tested in this research. The fracture mode of the alloys containing alloying elements less that 2.0 wt.% titanium and 0.5 wt.% carbon showed intercrystalline fracture at room temperature, while the alloys containing higher amounts of alloying elements showed transcrystalline fracture. All of the alloys showed creep or ductile rupture mode at elevated temperature.

• 한국산업융합학회 논문집
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• 제26권2_2호
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• pp.333-340
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• 2023

Environmental regulations are being strengthened worldwide to solve global warming. For this reason, interest in eco-friendly gas fuels such as LNG and hydrogen is continuously increasing. However, when adopting eco-friendly gas fuel, liquefying at a cryogenic temperature is essential to ensure economic feasibility in storage and transportation. Although austenitic stainless steel is typically applied to store cryogenic liquefied gas, structural steel can experience sudden heat shrinkage in the case of leakage in the loading and unloading process of LNG. In severe cases, the phase of the steel may change, so care is required. This study conducted Charpy impact tests on steel material in nine different temperature ranges, from room to cryogenic temperatures, to analyze the effects of cryogenic liquefied gas leaks. As a result of the study, it was not easy to find variations in ductile to brittle transition temperature (DBTT) due to the leakage of cryogenic liquefied gas. Still, the overall impact toughness tended to decrease, and these results were verified through fracture surface analysis. In summary, brittle fracture of the steel plate may occur when a secondary load is applied to steel for hull structural use exposed to a cryogenic environment of -40 ℃ or lower. Therefore, it needs to be considered in the ship design and operating conditions.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 The 8th Asian Symposium on Precision Forging ASPF
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• pp.36-39
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• 2003

Due to the strength and biocompatibility requirement, the stainless steel SUS 316L is widely used for trauma internal fixation device. SUS 316L can be hardened and strengthened only by cold work. In this work, the material compression test is performed both in laboratory and computer simulation by a FEM analysis software DEFORM to correlate the hardness to strain. This data is then used for preform design and predict the hardness of the finish bone plate forging. Finally, we compared the hardness between the actual forging and computer analysis results. Although the predicted hardness from computer simulation. is 55HV higher than the final forging sample, we can get good compatibility on the hardening tendency of cold forging.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 추계학술대회 논문집
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• pp.29-29
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• 2007

본 연구에서는 분산강화 스테인리스강을 이용하여 케비테이션 발생 시 고체입자충격에 의한 재료의 침식메커니즘 및 침식저항성을 고찰하고자 하였다. 케비테이션 시간에 따른 침식저항성 측정결과, 기존재료에 비해 분산강화된 시편의 무게손실량이 낮았으며 침식잠복기가 짧고 침식속도가 낮아 전반적으로 우수한 저항성을 보였다. 이것은 침식표면의 손상메커니즘 관찰을 통해 확인할 수 있었다.