• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.451-459
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• 2011

Austenitic stainless steels of 300 series are widely used as the structural material due to excellent their cryogenic mechanical properties at cryogenic temperature. There are 316 steel which molybdenum is added to improve the austenitic stability, 316L which carbon contents is reduced to decrease the grain boundary precipitation during welding process, and 316LN which nitrogen is added to improve the austenitic stability and the mechanical strength. But material researches for the welding conditions and mechanical properties at the cryogenic temperature were insufficient so far. In this paper, the characteristics of mechanical properties considering the effect of welding conditions and cryogenic temperature are studied.

• Journal of Advanced Marine Engineering and Technology
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• v.15 no.4
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• pp.22-28
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• 1991

The crevice corrosion behavior on austenitic AISI 304 and 316L stainless steel welded by TIG, MIG, $CO_2$ and SMA was studied. The results are as follows : In 10% $FeCl_3$ solution and natural sea water sampled near Mokpo port, the base metal of 304 stainless steel showed small amount corrosion, whereas 316L stainless steel did not showed any corrosion in the test periods. The weight loss caused by crevice corrosion increased with increasing weld heat input and residual .delta. ferrite formed in welded part. The corrosion resistance of the welded part was in the order of TIG, MIG, $CO_2$ and SMA. From this tendency, it is proved that the smaller heat input gives the better corrosion resistance.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.175-177
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• 1994

The wear corrosion behaviour of a nitrogen ion implanted super stainless steel (S.S.S, 22Cr - 20Ni - 6Mo - 0.25N) was compared with those of S.S.S, 316L SS and TiN coated 316L SS. The Cr and Ni amounts won out from the materials were investigated using an electrothermal atomic absorption spectrometry. We observed that the Cr dissolution rate of the S.S.S was similar to that of 316L SS, however, the Ni release of the S.S.S was feater than 316L SS. The metal ions released from the nitrogen ion implanted S.S.S surface were significantly reduced. The wear corrosion behaviour of the stainless steels was not correlated with the results shown by a static metal ion release test.

• Journal of Power System Engineering
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• v.18 no.3
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• pp.100-105
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• 2014

This study is to investigate the effect of thermo mechanical treatment on the mechanical properties of 316L stainless steel. ${\alpha}^{\prime}$ and ${\varepsilon}$-martensite was formed by deformation. With increasing number of thermo mechanical treatment, volume fraction of martensite was increased rapidly, and then unchanged. With increasing number of thermo mechanical treatment, hardness and strength was increased rapidly, and then unchanged while elongation was decreased rapidly, and then unchanged. With increasing volume fraction of martensite formed by thermo mechanical treatment, hardness and strength was increased rapidly, elongation was decreased rapidly. Thus, hardness, strength and elongation of thermo mechanical treated 316L stainless steel was strongly affected by martensite formed by thermo mechanical treatment. Good combination of strength and elongation was obtained from thermomechanical treatment.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.2
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• pp.16-22
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• 2006

Stainless steel has widely been used in various industrial fields because it has high corrosion resistance. But, we have little design data about the creep life prediction of SUS316L stainless steel. Therefore, in this study, a series of creep tests and study on them under 16 constant stress and temperature combined conditions have been performed to get the creep design data and life prediction of SUS316L stainless steels and we have gotten the following results. First, the stress exponents decrease as the test temperatures increase. Secondly, the creep activation energy gradually decreases as the stresses become bigger. Thirdly, the constant of Larson-Miller parameters on this alloy is estimated about 10. And last, the creep rupture fractographs show the intergranular ductile fracture with many dimples.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.192-192
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• 2013

하이브리드 표면처리는 다른 표면처리법을 동시 또는 연속적으로 행하여 단일표면처리에 비해 더욱 우수한 특성을 부여시키기 위한 표면처리법이다. 본 연구는 붕소와 질소 원소를 이용한 하이브리드 표면처리를 오스테나이트계 스테인리스강인 STS 316L 소재에 적용하여 변화된 특성을 평가하였다. 본 실험에 사용된 하이브리드 표면처리법으로는 붕소분말을 이용한 보로나이징처리와 활성스크린을 이용한 이온질화처리법을 적용하였다. 하이브리드 표면처리된 STS 316L시편은 FE-SEM을 이용하여 표면형상 및 단면조직을 관찰하였으며 GDS와 XRD를 이용하여 깊이에 따른 원소 및 상분석을 실시하였다. 또한 마이크로비커스 경도계와 마모시험기를 이용하여 경도와 마모특성을 측정하였고, 염수분무시험을 통하여 해수환경에서 부식거동을 평가하였다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.3
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• pp.479-486
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• 2002

In this study, the progressive inelastic deformation, so called, thermal ratchet phenomenon which can occur in high temperature structures of liquid metal reactor was simulated with thermal ratchet structural test facility and 316L stainless steel test cylinder. The thermal ratchet deformation at the reactor baffle cylinder of the liquid metal reactor can occur due to the moving temperature distribution along the axial direction as the sodium free surface moves up and down under the cyclic heat-up and cool-down transients. The ratchet deformation was measured with the laser displacement sensor and LVDTs after cooling the structural specimen which is heated up to 55$0^{\circ}C$ with steep temperature gradients along the axial direction. The temperature distribution of the test cylinder along the axial direction was measured with 28 channels of thermocouples and was used for the ratchet analysis. The thermal ratchet deformation was analyzed with the constitutive equation of nonlinear combined hardening model which was implemented as ABAQUS user subroutine and the analysis results were compared with those of the test. Thermal ratchet load was applied 9 times and the residual displacement after 9 cycles of thermal load was measured to be 1.79mm. The ratcheting deformation shapes obtained by the analysis with the combined hardening model were in reasonable agreement with those of the structural tests.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1377-1382
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• 2011

Recently, alternative and novel energy resources have been developed for use in the future because of the current environmental problems and exhaustion of fossil energy resources. Hydrogen energy has many merits, such as its environmental friendliness, easy storage, and easy production, but it also has disadvantages, in that it is highly combustible and explosive. In this study, a test procedure using a simple SP test under highly pressurized hydrogen gas conditions was established. In order to evaluate its applicability, SP tests were carried out using a stainless steel (SUS316L) sample under atmospheric, pressurized helium, and pressurized hydrogen gas conditions. The results under the pressurized hydrogen gas condition showed fissuring and produced a reduction of the elongation in the plastic instability region due to hydrogen embrittlement, showing the effectiveness of the current in-situ SP test.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.132-134
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• 2007

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.19-24
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• 2004

A number of creep data were collected and filed for type 316LN stainless steels through literature survey and experimental data produced in KAERI. Using these data, polynomial equations for predicting creep life were obtained for Larson Miller (L-M), Qrr-Sherby-Dorn (O-S-D) and Manson-Haferd (M-H) parametric methods. In order to find out the suitability for them, the relative standard error (RSE) and standard error of estimate (SEE) values were obtained by statistical process of creep data. The O-S-D parameter showed better fitting to creep-rupture data than the L-M or the M-H parameters, and the three parametric methods did not generate the large difference in the SEE and the RSE values.