超级奥氏体不锈钢654SMO的研究进展
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摘要
超级奥氏体不锈钢具有十分优异的耐腐蚀性能和良好的综合力学性能,是高端装备制造业急需的关键材料之一。介绍了近年来作者在超级奥氏体不锈钢654SMO制备工艺、组织与性能和焊接技术方面的研究进展。开发出了铝+镍镁+稀土复合脱氧脱硫的超洁净度冶炼工艺。基于VOF多相流模型,计算了凝固过程Mo元素的偏析行为,提出适当提高冷却强度和降低浇铸温度可有效减轻宏观偏析。探索出了最佳热加工窗口,提出热加工窗口窄的主要原因为大量合金元素的固溶强化作用和高的析出敏感性。阐明了高温氧化机理,熔融MnMoO_4-MoO_3钼酸盐电化学反应和不连续Cr_2N析出的协同作用强烈促进灾难性氧化的发生。分析了时效析出热力学和时效析出行为,建立了评价晶间腐蚀敏感性的双环动电位再活化法,揭示了析出相周围贫铬区和贫钼区导致晶间腐蚀的机理。全面评价了钢的力学性能和典型服役环境中的腐蚀行为,指出654SMO力学性能优异,耐腐蚀性能可与镍基合金相媲美。利用氩气保护的FSW技术成功实现了654SMO(2.4 mm厚)的焊接,获得了高质量、无氮损、组织性能优异的焊件。
Super austenitic stainless steel exhibits excellent corrosion resistance and superior comprehensive mechanical properties, which is one of the short and urgent key materials in the advanced equipment manufacturing industry. The recent research of the authors' group on the manufacture process, microstructure and properties, and welding technology of super austenitic stainless steel 654 SMO were introduced. The ultra-clean smelting process of deoxidation and desulphurization with Al+Ni-Mg+RE were developed. Macro-segregation behavior of Mo element was calculated by VOF Multiphase Model. The results suggest that the macro-segregation can be released effectively by properly increasing the cooling intensity and decreasing the casting temperature. The optimum hot working window was proposed, and due to the effect of solid solution strengthening of the massive alloy elements and the high precipitation sensitivity, the hot working window is narrowed. The high temperature oxidation mechanism was clarified that the synergistic effects of the electrochemical reaction between the molten MnMoO_4-MoO_3 molybdate and the discontinuous Cr_2N precipitation strongly promote catastrophic oxidation. The aging precipitation thermodynamics and aging precipitation behavior were analyzed. A double loop potentiodynamic reactivation method for evaluating intergranular corrosion sensitivity were established. The mechanism of intergranular corrosion is attributed to the Cr and Mo depletion zone adjacent to the precipitates. The mechanical properties and corrosion behavior in typical service environments were evaluated comprehensively. The results indicate that 654 SMO has excellent mechanical properties, and its corrosion resistance is comparable to that of nickel-based alloys. The welding of 654 SMO(2.4 mm thick) was successfully realized by FSW technology. The weld with high quality, no nitrogen loss, excellent microstructure and properties were obtained.
Super austenitic stainless steel exhibits excellent corrosion resistance and superior comprehensive mechanical properties, which is one of the short and urgent key materials in the advanced equipment manufacturing industry. The recent research of the authors' group on the manufacture process, microstructure and properties, and welding technology of super austenitic stainless steel 654 SMO were introduced. The ultra-clean smelting process of deoxidation and desulphurization with Al+Ni-Mg+RE were developed. Macro-segregation behavior of Mo element was calculated by VOF Multiphase Model. The results suggest that the macro-segregation can be released effectively by properly increasing the cooling intensity and decreasing the casting temperature. The optimum hot working window was proposed, and due to the effect of solid solution strengthening of the massive alloy elements and the high precipitation sensitivity, the hot working window is narrowed. The high temperature oxidation mechanism was clarified that the synergistic effects of the electrochemical reaction between the molten MnMoO_4-MoO_3 molybdate and the discontinuous Cr_2N precipitation strongly promote catastrophic oxidation. The aging precipitation thermodynamics and aging precipitation behavior were analyzed. A double loop potentiodynamic reactivation method for evaluating intergranular corrosion sensitivity were established. The mechanism of intergranular corrosion is attributed to the Cr and Mo depletion zone adjacent to the precipitates. The mechanical properties and corrosion behavior in typical service environments were evaluated comprehensively. The results indicate that 654 SMO has excellent mechanical properties, and its corrosion resistance is comparable to that of nickel-based alloys. The welding of 654 SMO(2.4 mm thick) was successfully realized by FSW technology. The weld with high quality, no nitrogen loss, excellent microstructure and properties were obtained.
引文
[1] 孙长庆.超级奥氏体不锈钢的发展,性能与应用(上)[J].化工设备设计,1999,36(6):38.(Sun C Q.Development,performance and application of super austenitic stainless steel(Part 1)[J].Chemical Equipment Design,1999,36(6):38.)
[2] Plauta R L,Herrerab C,Escriba D M,et al.A short review on wrought austenitic stainless steels at high temperatures:Processing,microstructure,properties and performance[J].Materials Research,2007,10(4):453.
[3] Johansson E,Pettersson R,Mameng S,et al.UNS S32654 for demanding offshore applications[J].Journal of Welding and Joining,2015,33(5):393.
[4] 赵钦新,查爽,康子晋,等.冷凝式锅炉及工程应用[J].工业锅炉,2003(4):1.(Zhao Q X,Zha S,Kang Z J,et al.Condensing boiler and its application[J].Industrial Boiler,2003(4):1.)
[5] Zhu H C,Li H B,Zhang S C,et al.Numerical simulation of Mo macrosegregation during ingot casting of high-Mo austenitic stainless steel[J].Ironmaking and Steelmaking,2015,42(10):748.
[6] 高建兵,范思鹏,张树才,等.新型超级奥氏体不锈钢654SMO偏析行为及均匀化工艺[J].钢铁,2018,53(8):83.(Gao J B,Fan S P,Zhang S C,et al.Segregation behavior and homogenizing treatment of a new type super austenitic stainless steel 654SMO[J].Iron and Steel,2018,53(8):83.)
[7] Koutsoukis T,Redja?mia A,Fourlaris G.Phase transformations and mechanical properties in heat treated superaustenitic stainless steels[J].Materials Science and Engineering,2013,561A:477.
[8] Zhang S C,Jiang Z H,Li H B,et al.Detection of susceptibility to intergranular corrosion of aged super austenitic stainless steel S32654 by a modified electrochemical potentiokinetic reactivation method[J].Journal of Alloys and Compounds,2017,695:3083.
[9] 臧华勋,肖学山,童潮山,等.新型耐蚀超级奥氏体不锈钢中的高温析出相[J].钢铁研究学报,2009,21(2):44.(Zang H X,Xiao X S,Tong C S,et al.High temperature precipitated phases of new corrosion-resistant super austenitic-steel[J].Journal of Iron and Steel Research,2009,21(2):44.)
[10] Bradaskja B,Pirnar B,Fazarinc M,et al.Deformation behaviour and microstructural evolution during hot compression of AISI 904L[J].Steel Research International,2011,82(4):346.
[11] Pu E X,Zheng W J,Xiang J Z,et al.Hot working charact-eristic of superaustenitic stainless steel 254SMO[J].Acta Metallurgica Sinica,2014,27(2):313.
[12] Han Y,Wu H,Zhang W,et al.Constitutive equation and dynamic recrystallization behavior of as-cast 254SMO super-austenitic stainless steel[J].Materials and Design,2015,69:230.
[13] 曾莉,张威,王琦,等.超级奥氏体不锈钢的高温变形行为[J].钢铁,2017,52(10):72.(Zeng L,Zhang W,Wang Q,et al.Hot deformation behavior of super austenitic stainless steel[J].Iron and Steel,2017,52(10):72.)
[14] 任建斌,宋志刚,郑文杰,等.254SMo超级奥氏体不锈钢的热变形行为[J].钢铁研究学报,2012,24(5):41.(Ren J B,Song Z G,Zheng W J,et al.Hot deformation behavior of super austenitic stainless steel 254SMo[J].Journal of Iron and Steel Research,2012,24(5):41.)
[15] Pu E X,Feng H,Liu M,et al.Constitutive modeling for flow behaviors of superaustenitic stainless steel S32654 during hot deformation[J].Journal of Iron and Steel Research,International,2016,23(2):178.
[16] Sun H Y,Zhou Z J,Wang M,et al.Effect of thermomechanical parameters on Σ3n grain boundaries and grain boundary networks of a new superaustenitic stainless steel[J].Journal of Iron and Steel Research,International,2014,21(1):109.
[17] Zhang W,Zhang J,Han Y,et al.Metadynamic recrystallization behavior of as-cast 904L superaustenitic stainless steel[J].Journal of Iron and Steel Research,International,2016,23(2):151.
[18] Pu E X,Zheng W J,Song Z G,et al.Optimization of hot workability in superaustenitic stainless steel 654SMO[J].Journal of Iron and Steel Research,International,2014,21(10):975.
[19] Li H B,Zhang B B,Jiang Z H,et al.A new insight into high-temperature oxidation mechanism of superaustenitic stainless steel S32654 in air[J].Journal of Alloys and Compounds,2016,686:326.
[20] Olsson J,Wasielewska W.Applications and experience with a superaustenitic 7Mo stainless steels in hostile environments[J].Avesta Sheffield,1998(2):1.
[21] Li H B,Jiang Z H,Feng H,et al.Effect of temperature on the corrosion behaviour of super austenitic stainless steel S32654 in polluted phosphoric acid[J].International Journal of Electrochemical Science,2015,10:4832.
[22] 朗宇平,康喜范.超级高氮奥氏体不锈钢的耐腐蚀性能及氮的影响[J].钢铁研究学报,2001,13(1):30.(Lang Y P,Kang X F.Corrosion resistance of high nitrogen superaustenitic stainless steel and influence of nitrogen[J].Journal of Iron and Steel Research,2001,13(1):30.)
[23] Li H B,Yang S X,Zhang S C,et al.Microstructure evolution and mechanical properties of friction stir welding super-austenitic stainless steel S32654[J].Materials and Design,2017,118:207.
[24] 赵浩洋.高钼高氮超级奥氏体不锈钢热变形行为研究[D]//沈阳:东北大学,2014.(Zhao H Y.Research on Deformation Behavior of Super Austenitic Stainless Steel with High Mo and N[D]//Shenyang:Northeastern University,2014.)
[25] Momeni A,Dehghani K,Keshmiri H,et al.Hot deformation behavior and microstructural evolution of a superaustenitic stainless steel[J].Materials Science and Engineering,2010,527A(3):1605.
[26] Liu G W,Han Y,Shi Z Q,et al.Hot deformation and optimization of process parameters of an as-cast 6Mo superaustenitic stainless steel[J].Materials and Design,2014,53:662.
[27] Shaheen W M,Selim M M.Thermal decompositions of pure and mixed manganese carbonate and ammonium molybdate tetrahydrate[J].Journal of Thermal Analysis and Calorimetry,2000,59:961.
[28] Safikhani A,Esmailian M,Salmani M R,et al.Effect of Ni-Mo addition on cyclic and isothermal oxidation resistance and electrical behavior of ferritic stainless steel for SOFCs interconnect[J].International Journal of Hydrogen Energy,2014,39:11210.
[29] Ebrahimifar H,Zandrahimi M.Mn coating on AISI 430 ferritic stainless steel by pack cementation method for SOFC interconnect applications[J].Solid State Ionics,2011,183:71.
[30] Birks N,Meier G H,Pettit F S.Introduction to the High-Temperature Oxidation of Metals[M].2nd ed.Beijing:Higher Education Press,2010.
[31] Gao W,Li Z M.Developments in High Temperature Corrosion and Protection of Materials[M].New Zealand:Woodhead Publishing,2008.
[32] Yun D W,Seo H S,Jun J H,et al.Molybdenum effect on oxidation resistance and electric conduction of ferritic stainless steel for SOFC interconnect[J].International Journal of Hydrogen Energy,2012,37:10328.
[33] Cao Y,Norell M.Role of nitrogen uptake in oxidation of 304L and 904L austenitic stainless steels[J].Oxidation of Metals,2013,80:479.
[34] Zhang S C,Jiang Z H,Li H B,et al.Precipitation behavior and phase transformation mechanism of super austenitic stainless steel S32654 during isothermal aging[J].Materials Characterization,2018,137:244.
[35] Heino S.Role of Mo and W during sensitization of superaustenitic stainless steel crystallography and composition of precipitates[J].Metallurgical and Materials Transactions,2000,31A:1893.
[36] Song Z G,Pu E X.Precipitated phases of super austenitic stainless steel 654SMO[J].Journal of Iron and Steel Research,International,2017,24:743.
[37] Wallen B,Liljas M,Stenvall P.AVESTA 654 SMOTM-A new nitrogen-enhanced superaustenitic stainless steel[J].Materials and Corrosion,1993,44(3):83.
[38] 张树才,姜周华,李花兵,等.超级奥氏体不锈钢654SMO组织与性能研究[C]//第十届中国钢铁年会暨第六届宝钢学术年会论文集.上海:中国金属学会,2015:1.(Zhang S C,Jiang Z H,Li H B,et al.Research on the microstructure and properties of super austenitic stainless steel 654SMO[C]// Proceedings of the 10th CSM Steel Congress and the 6th Baosteel Biennial Academic Conference.Shanghai:The Chinese Society for Metals,2015:1.)
[39] Palit G C,Kain V,Gadiyar H S.Electrochemical investigations of pitting corrosion in nitrogen-bearing type 316LN stainless steel[J].Corrosion,1993,49(12):977.
[40] Sarlak H,Atapour M,Esmailzadeh M.Corrosion behavior of friction stir welded lean duplex stainless steel[J].Materials and Design,2015,66:209.
[41] Song K H,Fujii H,Nakata K.Effect of welding speed on microstructural and mechanical properties of friction stir welded Inconel 600[J].Materials and Design,2009,30:3972.
[42] Mehranfar M,Dehghani K.Producing nanostructured super-austenitic steels by friction stir processing[J].Materials Science and Engineering,2011,528A:3404.
[43] Mironov S,Sato Y S,Kokawa H,et al.Structural response of superaustenitic stainless steel to friction stir welding[J].Acta Materialia,2011,59:5472.
[44] Sato Y S,Harayama N,Kokawa H,et al.Evaluation of microstructure and properties in friction stirwelded superaustenitic stainless steel[J].Science and Technology of Welding and Joining,2009,14:202.
[45] Esmailzadeh M,Shamanian M,Kermanpur A,et al.Microstructure and mechanical properties of friction stir welded lean duplex stainless steel[J].Materials Science and Engineering,2013,561A:486.
[46] Du D X,Fu R D,Li Y J,et al.Gradient characteristics and strength matching in friction stir welded joints of Fe-18Cr-16Mn-2Mo-0.85N austenitic stainless steel[J].Materials Science and Engineering,2014,616A:246.
[2] Plauta R L,Herrerab C,Escriba D M,et al.A short review on wrought austenitic stainless steels at high temperatures:Processing,microstructure,properties and performance[J].Materials Research,2007,10(4):453.
[3] Johansson E,Pettersson R,Mameng S,et al.UNS S32654 for demanding offshore applications[J].Journal of Welding and Joining,2015,33(5):393.
[4] 赵钦新,查爽,康子晋,等.冷凝式锅炉及工程应用[J].工业锅炉,2003(4):1.(Zhao Q X,Zha S,Kang Z J,et al.Condensing boiler and its application[J].Industrial Boiler,2003(4):1.)
[5] Zhu H C,Li H B,Zhang S C,et al.Numerical simulation of Mo macrosegregation during ingot casting of high-Mo austenitic stainless steel[J].Ironmaking and Steelmaking,2015,42(10):748.
[6] 高建兵,范思鹏,张树才,等.新型超级奥氏体不锈钢654SMO偏析行为及均匀化工艺[J].钢铁,2018,53(8):83.(Gao J B,Fan S P,Zhang S C,et al.Segregation behavior and homogenizing treatment of a new type super austenitic stainless steel 654SMO[J].Iron and Steel,2018,53(8):83.)
[7] Koutsoukis T,Redja?mia A,Fourlaris G.Phase transformations and mechanical properties in heat treated superaustenitic stainless steels[J].Materials Science and Engineering,2013,561A:477.
[8] Zhang S C,Jiang Z H,Li H B,et al.Detection of susceptibility to intergranular corrosion of aged super austenitic stainless steel S32654 by a modified electrochemical potentiokinetic reactivation method[J].Journal of Alloys and Compounds,2017,695:3083.
[9] 臧华勋,肖学山,童潮山,等.新型耐蚀超级奥氏体不锈钢中的高温析出相[J].钢铁研究学报,2009,21(2):44.(Zang H X,Xiao X S,Tong C S,et al.High temperature precipitated phases of new corrosion-resistant super austenitic-steel[J].Journal of Iron and Steel Research,2009,21(2):44.)
[10] Bradaskja B,Pirnar B,Fazarinc M,et al.Deformation behaviour and microstructural evolution during hot compression of AISI 904L[J].Steel Research International,2011,82(4):346.
[11] Pu E X,Zheng W J,Xiang J Z,et al.Hot working charact-eristic of superaustenitic stainless steel 254SMO[J].Acta Metallurgica Sinica,2014,27(2):313.
[12] Han Y,Wu H,Zhang W,et al.Constitutive equation and dynamic recrystallization behavior of as-cast 254SMO super-austenitic stainless steel[J].Materials and Design,2015,69:230.
[13] 曾莉,张威,王琦,等.超级奥氏体不锈钢的高温变形行为[J].钢铁,2017,52(10):72.(Zeng L,Zhang W,Wang Q,et al.Hot deformation behavior of super austenitic stainless steel[J].Iron and Steel,2017,52(10):72.)
[14] 任建斌,宋志刚,郑文杰,等.254SMo超级奥氏体不锈钢的热变形行为[J].钢铁研究学报,2012,24(5):41.(Ren J B,Song Z G,Zheng W J,et al.Hot deformation behavior of super austenitic stainless steel 254SMo[J].Journal of Iron and Steel Research,2012,24(5):41.)
[15] Pu E X,Feng H,Liu M,et al.Constitutive modeling for flow behaviors of superaustenitic stainless steel S32654 during hot deformation[J].Journal of Iron and Steel Research,International,2016,23(2):178.
[16] Sun H Y,Zhou Z J,Wang M,et al.Effect of thermomechanical parameters on Σ3n grain boundaries and grain boundary networks of a new superaustenitic stainless steel[J].Journal of Iron and Steel Research,International,2014,21(1):109.
[17] Zhang W,Zhang J,Han Y,et al.Metadynamic recrystallization behavior of as-cast 904L superaustenitic stainless steel[J].Journal of Iron and Steel Research,International,2016,23(2):151.
[18] Pu E X,Zheng W J,Song Z G,et al.Optimization of hot workability in superaustenitic stainless steel 654SMO[J].Journal of Iron and Steel Research,International,2014,21(10):975.
[19] Li H B,Zhang B B,Jiang Z H,et al.A new insight into high-temperature oxidation mechanism of superaustenitic stainless steel S32654 in air[J].Journal of Alloys and Compounds,2016,686:326.
[20] Olsson J,Wasielewska W.Applications and experience with a superaustenitic 7Mo stainless steels in hostile environments[J].Avesta Sheffield,1998(2):1.
[21] Li H B,Jiang Z H,Feng H,et al.Effect of temperature on the corrosion behaviour of super austenitic stainless steel S32654 in polluted phosphoric acid[J].International Journal of Electrochemical Science,2015,10:4832.
[22] 朗宇平,康喜范.超级高氮奥氏体不锈钢的耐腐蚀性能及氮的影响[J].钢铁研究学报,2001,13(1):30.(Lang Y P,Kang X F.Corrosion resistance of high nitrogen superaustenitic stainless steel and influence of nitrogen[J].Journal of Iron and Steel Research,2001,13(1):30.)
[23] Li H B,Yang S X,Zhang S C,et al.Microstructure evolution and mechanical properties of friction stir welding super-austenitic stainless steel S32654[J].Materials and Design,2017,118:207.
[24] 赵浩洋.高钼高氮超级奥氏体不锈钢热变形行为研究[D]//沈阳:东北大学,2014.(Zhao H Y.Research on Deformation Behavior of Super Austenitic Stainless Steel with High Mo and N[D]//Shenyang:Northeastern University,2014.)
[25] Momeni A,Dehghani K,Keshmiri H,et al.Hot deformation behavior and microstructural evolution of a superaustenitic stainless steel[J].Materials Science and Engineering,2010,527A(3):1605.
[26] Liu G W,Han Y,Shi Z Q,et al.Hot deformation and optimization of process parameters of an as-cast 6Mo superaustenitic stainless steel[J].Materials and Design,2014,53:662.
[27] Shaheen W M,Selim M M.Thermal decompositions of pure and mixed manganese carbonate and ammonium molybdate tetrahydrate[J].Journal of Thermal Analysis and Calorimetry,2000,59:961.
[28] Safikhani A,Esmailian M,Salmani M R,et al.Effect of Ni-Mo addition on cyclic and isothermal oxidation resistance and electrical behavior of ferritic stainless steel for SOFCs interconnect[J].International Journal of Hydrogen Energy,2014,39:11210.
[29] Ebrahimifar H,Zandrahimi M.Mn coating on AISI 430 ferritic stainless steel by pack cementation method for SOFC interconnect applications[J].Solid State Ionics,2011,183:71.
[30] Birks N,Meier G H,Pettit F S.Introduction to the High-Temperature Oxidation of Metals[M].2nd ed.Beijing:Higher Education Press,2010.
[31] Gao W,Li Z M.Developments in High Temperature Corrosion and Protection of Materials[M].New Zealand:Woodhead Publishing,2008.
[32] Yun D W,Seo H S,Jun J H,et al.Molybdenum effect on oxidation resistance and electric conduction of ferritic stainless steel for SOFC interconnect[J].International Journal of Hydrogen Energy,2012,37:10328.
[33] Cao Y,Norell M.Role of nitrogen uptake in oxidation of 304L and 904L austenitic stainless steels[J].Oxidation of Metals,2013,80:479.
[34] Zhang S C,Jiang Z H,Li H B,et al.Precipitation behavior and phase transformation mechanism of super austenitic stainless steel S32654 during isothermal aging[J].Materials Characterization,2018,137:244.
[35] Heino S.Role of Mo and W during sensitization of superaustenitic stainless steel crystallography and composition of precipitates[J].Metallurgical and Materials Transactions,2000,31A:1893.
[36] Song Z G,Pu E X.Precipitated phases of super austenitic stainless steel 654SMO[J].Journal of Iron and Steel Research,International,2017,24:743.
[37] Wallen B,Liljas M,Stenvall P.AVESTA 654 SMOTM-A new nitrogen-enhanced superaustenitic stainless steel[J].Materials and Corrosion,1993,44(3):83.
[38] 张树才,姜周华,李花兵,等.超级奥氏体不锈钢654SMO组织与性能研究[C]//第十届中国钢铁年会暨第六届宝钢学术年会论文集.上海:中国金属学会,2015:1.(Zhang S C,Jiang Z H,Li H B,et al.Research on the microstructure and properties of super austenitic stainless steel 654SMO[C]// Proceedings of the 10th CSM Steel Congress and the 6th Baosteel Biennial Academic Conference.Shanghai:The Chinese Society for Metals,2015:1.)
[39] Palit G C,Kain V,Gadiyar H S.Electrochemical investigations of pitting corrosion in nitrogen-bearing type 316LN stainless steel[J].Corrosion,1993,49(12):977.
[40] Sarlak H,Atapour M,Esmailzadeh M.Corrosion behavior of friction stir welded lean duplex stainless steel[J].Materials and Design,2015,66:209.
[41] Song K H,Fujii H,Nakata K.Effect of welding speed on microstructural and mechanical properties of friction stir welded Inconel 600[J].Materials and Design,2009,30:3972.
[42] Mehranfar M,Dehghani K.Producing nanostructured super-austenitic steels by friction stir processing[J].Materials Science and Engineering,2011,528A:3404.
[43] Mironov S,Sato Y S,Kokawa H,et al.Structural response of superaustenitic stainless steel to friction stir welding[J].Acta Materialia,2011,59:5472.
[44] Sato Y S,Harayama N,Kokawa H,et al.Evaluation of microstructure and properties in friction stirwelded superaustenitic stainless steel[J].Science and Technology of Welding and Joining,2009,14:202.
[45] Esmailzadeh M,Shamanian M,Kermanpur A,et al.Microstructure and mechanical properties of friction stir welded lean duplex stainless steel[J].Materials Science and Engineering,2013,561A:486.
[46] Du D X,Fu R D,Li Y J,et al.Gradient characteristics and strength matching in friction stir welded joints of Fe-18Cr-16Mn-2Mo-0.85N austenitic stainless steel[J].Materials Science and Engineering,2014,616A:246.