• Title/Summary/Keyword: AISI 316L

Search Result 48, Processing Time 0.049 seconds

The low temperature plasma nitrocarburizng of AISI304L and AISI316L stainless steel (AISI304L과 AISI316L강의 저온프라즈마 질탄화 처리 )

  • Jeong, Gwang-Ho;Lee, In-Seop
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2007.11a
    • /
    • pp.153-154
    • /
    • 2007
  • AISI316L강은 AISI304L강과 기본 조성은 같지만 316L강이 약 2.5%의 Mo가 첨가되어 있다. 저온 플라즈마 질탄화 시 모재에 첨가된 Mo의 영향을 조사하기 위하여 처리온도를 변화시켜 실험하였다. 같은 처리온도의 경우 경화층의 두께는 316L강이 비교적 두껍게 형성되었다. 316L강의 경우 $450^{\circ}C$이하에서 약 25 ${\mu}m$까지 형성되었고, 306L강의 경우 $400^{\circ}C$에서 약 10 ${\mu}m$까지 형성되었다. $400^{\circ}C$ 이하에서 경화층은 두 가지시편 모두 확장된 오스테나이트 (${\gamma}_N,\;{\gamma}_c$)로 이루어져 있으나, 304L의 경우 $430^{\circ}C$부터 석출물(CrN)이 형성되기 시작하였다. 316L의 경우 $450^{\circ}C$까지 석출물이 형성되지 않았고, $480^{\circ}C$에서 석출물 (CrN)이 관찰되었다. 석출물이 형성된 시편을 제외한 모든 시편의 내식성은 모제보다 증가 하였다.

  • PDF

Effect of Stress Relieving Heat Treatment on Tensile and Impact Toughness Properties of AISI 316L Alloy Manufactured by Selective Laser Melting Process (선택적 레이저 용융 공정으로 제조된 AISI 316L 합금의 인장 및 충격 인성 특성에 미치는 응력 완화 열처리의 영향)

  • Yang, Dong-Hoon;Ham, Gi-Su;Park, Sun-Hong;Lee, Kee-Ahn
    • Journal of Powder Materials
    • /
    • v.28 no.4
    • /
    • pp.301-309
    • /
    • 2021
  • In this study, an AISI 316 L alloy was manufactured using a selective laser melting (SLM) process. The tensile and impact toughness properties of the SLM AISI 316 L alloy were examined. In addition, stress relieving heat treatment (650℃ / 2 h) was performed on the as-built SLM alloy to investigate the effects of heat treatment on the mechanical properties. In the as-built SLM AISI 316 L alloy, cellular dendrite and molten pool structures were observed. Although the molten pool did not disappear following heat treatment, EBSD KAM analytical results confirmed that the fractions of the low- and high-angle boundaries decreased and increased, respectively. As the heat treatment was performed, the yield strength decreased, but the tensile strength and elongation increased only slightly. Impact toughness results revealed that the impact energy increased by 33.5% when heat treatment was applied. The deformation behavior of the SLM AISI 316 L alloy was also examined in relation to the microstructure through analyses of the tensile and impact fracture surfaces.

Evaluations of Microstructure and Electrochemical Anodic Polarization of AISI 304L and AISI 316L Stainless Steel Weld Metals with Creq/Nieq Ratio (Creq/Nieq비에 따른 AISI 304L 및 AISI 316L 스테인리스강 용접부의 미세조직 및 전기화학적 양극분극 평가)

  • Kim, Yeon Hee;Jang, Ah Young;Kang, Dong Hoon;Ko, Dae Eun;Shin, Yong Taek;Lee, Hae Woo
    • Korean Journal of Metals and Materials
    • /
    • v.48 no.12
    • /
    • pp.1090-1096
    • /
    • 2010
  • This pitting corrosion study of welded joints of austenitic stainless steels (AISI 304L and 316L) has addressed the differentiating solidification mode using three newly introduced filler wires with a flux-cored arc welding process (FCAW). The delta ferrite (${\delta}$-ferrite) content in the welded metals increased with an increasing equivalent weight ratio of chromium/nickel ($Cr_{eq}/Ni_{eq}$). Ductility dip cracking (DDC) was observed in the welded metal containing ferrite with none of AISI 304L and 0.1% of AISI 316L. The potentiodynamic anodic polarization results revealed that the $Cr_{eq}/Ni_{eq}$ ratio in a 3.5% NaCl solution didn't much affect the pitting potential ($E_{pit}$). The AISI 316L welded metals with ${\ddot{a}}$-ferrite content of over 10% had a superior $E_{pit}$ value. Though the AISI 316L welded metal with 0.1% ferrite had larger molybdenum contents than AISI 304L specimens, it showed a similar $E_{pit}$ value because the concentration of chloride ions and the corrosion product induced severe damage near the DDC.

Electrochemical Corrosion Characteristics of AISI-type 316 L Stainless Steel in Anode-Gas Environment of MCFC (용융탄산염 연료전지의 Anode가스 분위기에서 AISI-type 316L stainless steel의 전기화학적 부식 특성)

  • Lee, Kab-Soo;Lim, Tae-Hoon;Hong, Seong-Ahn;Kim, Hwa-Yong
    • Journal of the Korean Electrochemical Society
    • /
    • v.5 no.2
    • /
    • pp.62-67
    • /
    • 2002
  • The corrosion of the metallic cell components is blown to be one of the major reason f3r the performance degradation and subsequently the life-time limitation of the MCFC. To elucidate the corrosion phenomena, a corrosion study with the AISI-type 316L stainless steel, the most widely used separator material, in 621Li/38K carbonate eutectic melt was carried out. Corrosion phenomena in an MCFC were observed to differ from one location to another due to different environmental condition. The stability of passive film was found to be responsible fur the variations in corrosion phenomena. According to the potentiodynamic analysis, the passive film formed in anode-gas environment was less stable than in cathode-gas environment. The potentiostatic method combined with XRD analysis in addition to the cyclicvoltammetry was conducted to get an insight on variety corrosion reaction of AISI-type 316L stainless steel in a carbonate melt.

Effect of Friction Coefficient on the Small Punch Creep Behavior of AISI 316L Stainless Steel (AISI 316L스테인리스강의 소형펀치 크리프 거동에 미치는 마찰계수의 영향)

  • Kim, Bum-Joon;Cho, Nam-Hyuck;Kim, Moon-K;Lim, Byeong-Soo
    • Korean Journal of Metals and Materials
    • /
    • v.49 no.7
    • /
    • pp.515-521
    • /
    • 2011
  • Small punch creep testing has received attention due to the convenience of using smaller specimens than those of conventional uniaxial creep tests, which enables creep testing on developing or currently operational components. However, precedent studies have shown that it is necessary to consider friction between the punch and specimen when computing uniaxial equivalent stress from a finite element model. In this study, small punch creep behaviors of AISI 316L stainless steel, which is widely used in high temperature-high pressure machineries, have been compared for the two different ceramic balls such as $Si_3N_4$ and $Al_2O_3$. The optimal range of the friction coefficient is 0.4~0.5 at $650^{\circ}C$ for the best fit between experimental and simulation data of AISI 316 L stainless steel. The higher the friction coefficient, the longer the creep rupture time is. Therefore, the type of ceramic ball used must be specified for standardization of small punch creep testing.

Pulsed Bias Inductively Coupled Plasma Nitriding of Chromium Electroplated AISI 316L Stainless Steel for PEMFC Application (고분자 전해질 연료전지에 적용하기 위한 크롬 도급 AISI 316L 스테인리스강의 펄스 바이어스 유도결합 플라즈마 질화)

  • Kim, Min-U;Han, Dong-Hun;Hong, Won-Hyeok;Lee, Jeong-Jung
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2009.05a
    • /
    • pp.145-146
    • /
    • 2009
  • 크롬 도금된 AISI 316L 스테인리스강에 펄스 바이어스를 사용한 유도결합 플라즈마로 질화 처리하여 고분자 전해질 연료전지용 분리판에 적합한 물성을 확인하였다.

  • PDF

The corrosion and electrical property of AISI 316L by plasma nitriding (플라즈마 질화처리를 이용한 AISI 316L의 부식특성과 전기적 특성 분석)

  • Hong, Won-Hyeok;Han, Dong-Hun;Choe, Hyo-Seok;Lee, Jeong-Jung
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2009.05a
    • /
    • pp.147-148
    • /
    • 2009
  • 스테인리스강인 AISI 316L의 질화처리를 통하여 고분자 전해질 연료전지에 분리판에 적용가능한 특성을 측정하였다. 질화처리를 통하여 면간접촉저항을 $20m{\Omega}cm^2$ 정도로 낮게 만들었으며 부식특성도 원래의 스테인리스강과 비슷한 값을 나타내었다.

  • PDF