• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 춘계학술대회 논문집
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• pp.68-74
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• 2002

The tensile tests to identify the statistical tensile properties and the acoustic emission characteristics were conducted for STS304 stainless steel at $600^{\circ}C,\;700^{\circ}C$. From tensile tests performed by constant cross head speed controls with 1mm/min, rates at each elevated temperature, the scatters were observed in tensile strength, reduction of area, elongation and the acoustic emission parameters. The effect of temperature on the scatter of tensile behavior was larger at $700^{\circ}C$. The distributions of tensile properties was well followed in 3-parameter Weibull. The AE counts and energy of the $700^{\circ}C$ specimens were smaller than the $600^{\circ}C$.

• 동력기계공학회지
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• 제19권5호
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• pp.73-79
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• 2015

The effects of hydrogen charging on the mechanical properties of 304 stainless steels were investigated in conjunction with the detailed examinations of their fracture modes. The dependence of the absorbed impact energy and the surface hardness of the 304 stainless steels on the hydrogen charging time was characterized. The tensile properties of the 304 stainless steels by the variation of cross-head speed were also evaluated at the room temperature. The hydrogen charging was performed by an electrolysis method for all specimens of the 304 stainless steels. The mechanical properties of the 304 stainless steels exhibited the sensitivity of embrittlement due to a hydrogen charging. The correlation between mechanical properties and fracture surfaces was discussed.

• Steel and Composite Structures
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• 제25권3호
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• pp.327-335
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• 2017

To gain more knowledge of aluminum foam sandwich structure and promote the engineering application, aluminum foam sandwich consisting of 7050 matrix aluminum foam core and 304 stainless steel face-sheets was studied under three-point bending by WDW-T100 electronic universal tensile testing machine in this work. Results showed that when aluminum foam core was reinforced by 304 steel face-sheets, its load carrying capacity improved dramatically. The maximum load of AFS in three-point bending increased with the foam core density or face-sheet thickness monotonically. And also when foam core was reinforced by 304 steel panels, the energy absorption ability of foam came into play effectively. There was a clear plastic platform in the load-displacement curve of AFS in three-point bending. No crack of 304 steel happened in the present tests. Two collapse modes appeared, mode A comprised plastic hinge formation at the mid-span of the sandwich beam, with shear yielding of the core. Mode B consisted of plastic hinge formation both at mid-span and at the outer supports.

• 국제강구조저널
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• 제18권4호
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• pp.1139-1152
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• 2018

Many studies on the application of stainless steels as structural materials in buildings and infra-structures have been performed thanks to superior characteristics of corrosion resistance, fire resistance and aesthetic appeal. Experimental investigation to estimate the ultimate strength and fracture mode of the fillet-welded connections of cold-formed austenitic stainless steel (STS304L) with better intergranular corrosion resistance than that of austenitic stainless steel, STS304 commonly used has carried out by authors. Specimens were fabricated to fail by base metal fracture not weld metal fracture with main variables of weld lengths according to loading direction. All specimens showed a block shear fracture mode. In this paper, finite element analysis model was developed to predict the ultimate behaviors of welded connection and its validity was verified through the comparison with test results. Since the block shear behavior of welded connection due to stress triaxiality and shear-lag effects is different from that of bolted connection, stress and strain distributions in the critical path of tensile and shear fracture section were investigated. Test and analysis strengths were compared with those by current design specifications such as AISC, EC3 and existing researcher's proposed equations. In addition, through parametric analysis with extended variables, the conditions of end distance and longitudinal weld length for block shear fracture and tensile fracture were suggested.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.382-384
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• 2009

Strengthening mechanisms of metastable austenitic stainless steel, containing $\alpha'$-martensite phase, during strain aging was investigated. The variations of volume fraction of $\alpha'$-martensite phase, hardness of $\alpha'$-martensite phase, hardness of austenite were examined.

• 한국가스학회지
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• 제9권4호
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• pp.6-10
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• 2005

이 논문은 비저항에 따른 가스보일러용 오스테나이트계 스테인리스강(STS304)재의 손상거동에 관해 연구하기 위하여, 비저항에 따른 전기화학적 분극시험을 수행하였다. 그리고 비저항에 따른 가스보일러용 STS304강의 양극분극특성 및 손상거동인 공식양상을 고찰하였다. 비저항이 감소할수록 STS304강의 부동태유지전류밀도는 증가하고 부동태영역은 작아지고 있으며, 관통전위는 낮아지고 있다 또한 비저항이 가장 높은 $74{\Omega}{\cdot}m$중에서 손상거동인 공식양상은 거의 나타나지 않고, 비저항이 낮아질수록 손상거동인 공식양상은 더욱 성장되고, 공식수가 점점 증가하는 경향을 보이고 있다.

• Korean Journal of Acupuncture
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• 제24권1호
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• pp.59-63
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• 2007

Objectives : To discuss the biocompatibility of stainless steel for using acupuncture needles. Results and Conclusions : It is widely assumed that stainless steel is one of the good corrosion-resistant materials and is safe for human body, Most of metal acupuncture needles are made of STS304 and STS316 in light of human body safety: STS304 in more differences between STS304 and STS316 in light of human body safety: STS304 is more vulnerable to oxidation than STS316. A variety of literature survey showed that although STS316 is more corrosion-resistant than STS304 there is no evidence supporting the hypothesis that STS304 has the potential danger to human body, Further study would be necessary to draw more decisive conclusion.

• 한국전산구조공학회논문집
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• 제27권4호
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• pp.265-271
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• 2014

304L 스테인리스강판은 멤브레인타입 LNG선 단열시스템의 1차 방벽으로 이용된다. 304L 스테인리스강은 변태유기소성(TRIP)강으로 복잡한 재료거동을 보이는데, 이는 소성변형이 발생하는 동안 상변태를 경험하기 때문이다. 본 연구에서는 304L 스테인리스 강의 비선형 기계적 거동분석을 위한 온도의존 일축인장시험을 수행하였으며 재료의 파단이나 비선형 거동을 예측하기 위한 점소성모델을 제안하였다. 수치해석의 결과와 시험 결과를 비교 분석하여 유효성을 검증하였으며 LNG 멤브레인에 대한 적용성을 검토하기 멤브레인 구조시편을 제작하여 구조해석 및 유한요소해석을 수행하였다. 재료모델은 개발 서브루틴을 이용하였으며 ABAQUS 사용자지정 재료 서브루틴을 탑재한 유한요소해석 결과와 극저온 구조인장시험을 수행한 결과를 비교하여 구조적용성을 검증하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2005년도 추계학술강연 및 발표대회강연 및 발표논문 초록집
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• pp.90-90
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• 2005

• Steel and Composite Structures
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• 제32권6호
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• pp.701-715
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• 2019

Using first-order shear deformation theory (FSDT), a semi-analytical solution is employed to analyze creep damage and remaining life assessment of 304L austenitic stainless steel thick (304L ASS) cylindrical pressure vessels with variable thickness subjected to the temperature gradient and internal non-uniform pressure. Damages are obtained in thick cylinder using Robinson's linear life fraction damage rule, and time to rupture and remaining life assessment is determined by Larson-Miller Parameter (LMP). The thermo-elastic creep response of the material is described by Norton's law. The novelty of the present work is that it seeks to investigate creep damage and life assessment of the vessels with variable thickness made of 304L ASS using LMP based on first-order shear deformation theory. A numerical solution using finite element method (FEM) is also presented and good agreement is found. It is shown that temperature gradient and non-uniform pressure have significant influences on the creep damages and remaining life of the vessel.