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Microstructure Stability of V and Ta Microalloyed 12%Cr Reduced Activation Ferrite/Martensite Steel during Long-term Aging at 650℃ 被引量:5
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作者 Xiang Xiao Guoquan Liu +2 位作者 Benfu Hu Jinsan Wang Wenbin Ma 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第3期311-319,共9页
In view of developing novel alloys for applications in supercritical water-cooled reactor fuel cladding and in-core components, a 12%Cr reduced activation ferrite/martensite(RAFM) steel with good corrosion resistance ... In view of developing novel alloys for applications in supercritical water-cooled reactor fuel cladding and in-core components, a 12%Cr reduced activation ferrite/martensite(RAFM) steel with good corrosion resistance and irradiation performance was developed. V and Ta were added to form fine MX type carbonitrides and enhance the high temperature creep rupture strength. Microstructure stability of the steel during long-term aging at 650 C was studied experimentally combined with the simulation of ThermoCalc and DICTRA software. The results show that the precipitates in the steel during long-term aging contain M23C6, MX and Laves phase. M23C6 carbides play a major role in the stabilization of the tempered martensite lath structure by exerting a large Zener pinning force as compared with MX and Laves phase.Adding V and Ta in the steel can not only promote MX precipitation, but also refine M23C6 carbides and thus improve the thermal stability of lath/subgrains, which is beneficial to the improvement of high temperature microstructure stability of the 12%Cr RAFM steel. 展开更多
关键词 12%Cr reduced activation ferrite/martensite steel
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Strengthening mechanisms of reduced activation ferritic/martensitic steels:A review 被引量:6
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作者 Jin-hua Zhou Yong-feng Shen Nan Jia 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第3期335-348,共14页
This review summarizes the strengthening mechanisms of reduced activation ferritic/martensitic(RAFM)steels.High-angle grain boundaries,subgrain boundaries,nano-sized M_(23)C_(6),and MX carbide precipitates effectively... This review summarizes the strengthening mechanisms of reduced activation ferritic/martensitic(RAFM)steels.High-angle grain boundaries,subgrain boundaries,nano-sized M_(23)C_(6),and MX carbide precipitates effectively hinder dislocation motion and increase high-temperature strength.M23C6 carbides are easily coarsened under high temperatures,thereby weakening their ability to block dislocations.Creep properties are improved through the reduction of M23C6 carbides.Thus,the loss of strength must be compensated by other strengthening mechanisms.This review also outlines the recent progress in the development of RAFM steels.Oxide dispersion-strengthened steels prevent M23C6 precipitation by reducing C content to increase creep life and introduce a high density of nano-sized oxide precipitates to offset the reduced strength.Severe plastic deformation methods can substantially refine subgrains and MX carbides in the steel.The thermal deformation strengthening of RAFM steels mainly relies on thermo-mechanical treatment to increase the MX carbide and subgrain boundaries.This procedure increases the creep life of TMT(thermo-mechanical treatment)9Cr-1W-0.06Ta steel by~20 times compared with those of F82H and Eurofer 97 steels under 550℃/260 MPa. 展开更多
关键词 reduced activation ferritic/martensitic steel strengthening mechanism high-angle grain boundary subgrain boundary PRECIPITATE
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Designing a high Si reduced activation ferritic/martensitic steel for nuclear power generation by using Calphad method 被引量:4
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作者 Chao Liu Quanqiang Shi +4 位作者 Wei Yan Chunguang Shen Ke Yang Yiyin Shan Mingchun Zhao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第3期266-274,共9页
A high Si reduced activation ferritic/martensitic(RAFM) steel for nuclear structure application is successfully designed by using Calphad method. The main designed chemical composition is C 0.18–0.22%, Cr10.0–10.5%,... A high Si reduced activation ferritic/martensitic(RAFM) steel for nuclear structure application is successfully designed by using Calphad method. The main designed chemical composition is C 0.18–0.22%, Cr10.0–10.5%, W 1.0–1.5%, Si 1.0–1.3%, V+Ta 0.30–0.45%, and Fe in balance. High Si design brings excellent corrosion resistance, while low activation is advantageous in the nuclear waste processing. The experimental results indicate that the newly designed high Si RAFM steel had full martensitic structure and uniformly distributed fine second phase particles, and exhibited excellent mechanical properties and corrosion resistance. Compared to the P91 steel, this new RAFM steel designed by Calphad method is expected to be a promising candidate used in nuclear power generation, which also provides a new and effective approach to the development of RAFM steel for nuclear application. 展开更多
关键词 Ferritic/martensitic steel ALLOY design CALPHAD method reduced activation HIGH silicon
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强磁场对低活化钢中析出行为和力学性能的影响 被引量:5
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作者 夏志新 张弛 杨志刚 《金属学报》 SCIE EI CAS CSCD 北大核心 2011年第6期713-719,共7页
研究了在有、无外加磁场条件下热处理时,低活化钢中析出相的长大规律及其对力学性能的影响.经高温强磁场热处理后低活化钢的屈服强度和抗拉强度均比无磁场热处理时低,而冲击韧性并无明显变化.强磁场显著抑制M_(23)C_6(M=Cr,W和Fe)沿原... 研究了在有、无外加磁场条件下热处理时,低活化钢中析出相的长大规律及其对力学性能的影响.经高温强磁场热处理后低活化钢的屈服强度和抗拉强度均比无磁场热处理时低,而冲击韧性并无明显变化.强磁场显著抑制M_(23)C_6(M=Cr,W和Fe)沿原奥氏体晶界和马氏体板条界定向长大,强磁场下碳化物/铁素体界面能增大是导致长杆状M_(23)C_6碳化物球化的主要因素,并导致析出相颗粒密度降低,平均尺寸增大.利用Langer-Schwartz模型描述了低活化钢在高温强磁场条件下析出相的粗化过程.构建三维立体模型修正了屈服强度与沉淀强化关系的公式,定量描述了析出相的粗化过程对低活化钢力学性能的影响,模拟结果与实验结果符合较好. 展开更多
关键词 强磁场 低活化钢 碳化物 界面能 析出行为
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Atomistic study on the microscopic mechanism of grain boundary embrittlement induced by small dense helium bubbles in iron
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作者 Lei Peng Yong-Jie Sun +3 位作者 Jing-Yi Shi Yi-Fei Liu Shang-Ming Chen Liu-Liu Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期84-95,共12页
The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion reactors.In order to eluc... The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion reactors.In order to elucidate the susceptibility of different grain boundaries(GBs)to helium-induced embrittlement,the tensile fracture processes of 10 types of GBs with and without helium bubbles in body-centered cubic(bcc)iron at the relevant service temperature of 600 K were investigated via molecular dynamics methods.The results indicate that in the absence of helium bubbles,the GBs studied here can be classified into two distinct categories:brittle GBs and ductile GBs.The atomic scale analysis shows that the plastic deformation of ductile GB at high temperatures originates from complex plastic deformation mechanisms,including the Bain/Burgers path phase transition and deformation twinning,in which the Bain path phase transition is the most dominant plastic deformation mechanism.However,the presence of helium bubbles severely inhibits the plastic deformation channels of the GBs,resulting in a significant decrease in elongation at fractures.For bubble-decorated GBs,the ultimate tensile strength increases with the increase in the misorientation angle.Interestingly,the coherent twin boundary∑3{112}was found to maintain relatively high fracture strength and maximum failure strain under the influence of helium bubbles. 展开更多
关键词 Helium bubble Grain boundary EMBRITTLEMENT reduced activation ferritic martensitic steel Molecular dynamics Bain path
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低活化马氏体钢激光焊接接头的组织与性能 被引量:3
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作者 吴小虎 赵飞 +2 位作者 谢文佳 吕昌伟 梁任锦 《中国激光》 EI CAS CSCD 北大核心 2010年第2期577-580,共4页
对核聚变反应堆用低活化马氏体钢进行了激光焊接试验,并对焊接接头的显微组织和力学性能进行了测试分析。结果表明,对低活化马氏体钢进行激光焊接可以获得高质量的焊接接头;焊缝组织主要为板条状马氏体,硬度可达530 HV;热影响区(HAZ)包... 对核聚变反应堆用低活化马氏体钢进行了激光焊接试验,并对焊接接头的显微组织和力学性能进行了测试分析。结果表明,对低活化马氏体钢进行激光焊接可以获得高质量的焊接接头;焊缝组织主要为板条状马氏体,硬度可达530 HV;热影响区(HAZ)包括粗晶区和细晶区,粗晶区为粗大的珠光体,细晶区为细小的珠光体和铁素体的混合组织,最低硬度为220 HV;焊接接头有很好的力学性能,抗拉强度高达775 MPa。 展开更多
关键词 激光技术 激光焊接 低活化 马氏体钢 显微组织 力学性能
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Overview of the Research and Development for Reduced Activation Ferritic/Martensitic Steel CLF-1 被引量:3
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作者 WANG Pinghuai XU Zengyu +2 位作者 CHEN Jiming LIU Shi LI Xiongwei 《Southwestern Institute of Physics Annual Report》 2006年第1期162-163,共2页
Recent accomplishment by the SWIP for the reduced activation ferritic/martensitic steel CLF-1 development has been reviewed. It's found that CLF- 1 steel has better room temperature tensile properties than Eurofer97 ... Recent accomplishment by the SWIP for the reduced activation ferritic/martensitic steel CLF-1 development has been reviewed. It's found that CLF- 1 steel has better room temperature tensile properties than Eurofer97 steel and has a fully martensitic microstructure. 展开更多
关键词 reduced activation ferritic/martensitic steel Tensile properties Fully martensitic microstructure
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高温循环变形对JLF-1钢微观结构的影响 被引量:2
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作者 李怀林 西村新 +3 位作者 室贺健夫 长坂琢也 杨文 杨启法 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第2期252-257,共6页
低活性铁素体/马氏体钢,JLF-1,是聚变堆和超临界水冷堆的候选结构材料,高温循环软化现象是设计必须考虑的因素之一.为掌握JLF-1钢高温循环变形机理,本文采用透射电镜对JLF-1钢高温低周疲劳后样品的微观结构进行了分析,发现JLF-1钢的循... 低活性铁素体/马氏体钢,JLF-1,是聚变堆和超临界水冷堆的候选结构材料,高温循环软化现象是设计必须考虑的因素之一.为掌握JLF-1钢高温循环变形机理,本文采用透射电镜对JLF-1钢高温低周疲劳后样品的微观结构进行了分析,发现JLF-1钢的循环软化现象与位错密度、位错胞、板条宽度有关;其峰值拉应力与位错密度、板条宽度呈函数关系. 展开更多
关键词 低活性铁素体/马氏体钢 循环变形 微观结构 循环软化
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热轧形变量对低活化钢中MX析出行为的影响 被引量:2
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作者 韩小朋 王均安 +1 位作者 陈永充 姬鹏云 《金属热处理》 CAS CSCD 北大核心 2019年第3期108-113,共6页
研究了在950℃下热轧水淬的不同形变量的低活化钢中MX的析出行为。通过TEM观察了萃取复型得到的低活化钢中碳化物的变化,包括碳化物的种类、尺寸以及数量。结果表明:低活化钢在950℃热轧时,析出的碳化物稳定相是MX(M=V、Ta,X=C),主要是T... 研究了在950℃下热轧水淬的不同形变量的低活化钢中MX的析出行为。通过TEM观察了萃取复型得到的低活化钢中碳化物的变化,包括碳化物的种类、尺寸以及数量。结果表明:低活化钢在950℃热轧时,析出的碳化物稳定相是MX(M=V、Ta,X=C),主要是Ta C,少量为VC,形状都为球形。热轧细化了MX的尺寸,当形变量相对较小时,碳化物MX的平均尺寸在7~8 nm,形变量相对较大时,碳化物MX的平均尺寸在5~6 nm。当形变量达到50%时,碳化物MX的尺寸不再随着形变量的增大产生变化。不同形变量的低活化钢中都出现了MX的团聚,团聚的程度随着形变量增加呈上升趋势。团聚的程度对于低活化钢的显微硬度没有显著影响。 展开更多
关键词 低活化钢 热轧 形变量 MX 显微硬度
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表面纳米化对低活化钢的组织及其热稳定性的影响 被引量:2
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作者 柳文波 张弛 +3 位作者 杨志刚 夏志新 高古辉 翁宇庆 《金属学报》 SCIE EI CAS CSCD 北大核心 2013年第6期707-716,共10页
通过表面机械研磨处理(SMAT)在低活化铁素体钢的表面形成了一层纳米晶.TEM和XRD结果显示,SMAT后的表层组织为纳米晶.550℃的回火实验结果显示,SMAT后的纳米晶具有良好的热稳定性;回火120 min后的晶粒异常长大,回火240 min后的晶粒比较均... 通过表面机械研磨处理(SMAT)在低活化铁素体钢的表面形成了一层纳米晶.TEM和XRD结果显示,SMAT后的表层组织为纳米晶.550℃的回火实验结果显示,SMAT后的纳米晶具有良好的热稳定性;回火120 min后的晶粒异常长大,回火240 min后的晶粒比较均匀(约250 nm).SMAT后试样表层碳化物的衍射峰变宽变弱,表明SMAT过程中碳化物被细化,HRTEM观察显示SMAT后的表层组织中存在细小的MC类型碳化物;根据XRD结果,计算了M_(23)C_6和MC碳化物的晶格常数分别为1.0631和0.4306 nm.由于测试机理和测量深度不同以及纳米组织的尺寸随着深度变化,利用XRD和TEM检测的晶粒尺寸不同,而TEM照片能更准确地反应晶粒的实际尺寸. 展开更多
关键词 表面纳米化 热稳定性 低活化钢 碳化物分解
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中间热处理对低活化钢组织及力学性能的影响 被引量:1
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作者 邱国兴 李琦 +1 位作者 彭雷朕 曹磊 《钢铁》 CAS CSCD 北大核心 2023年第7期106-112,共7页
以“真空感应+电渣重熔”制备的含钇和钛低活化马氏体钢为研究对象,探索研究了N2-T(1050℃保温后炉冷+980℃保温后空冷+755℃回火)和N-N-T(1050℃正火+980℃正火+755℃回火)两种中间热处理工艺对材料微观组织和力学性能的影响。利用金... 以“真空感应+电渣重熔”制备的含钇和钛低活化马氏体钢为研究对象,探索研究了N2-T(1050℃保温后炉冷+980℃保温后空冷+755℃回火)和N-N-T(1050℃正火+980℃正火+755℃回火)两种中间热处理工艺对材料微观组织和力学性能的影响。利用金相显微镜对热处理钢组织进行了观察;利用透射电镜对钢中析出相进行分析统计;最后对试验钢硬度、拉伸和冲击性能进行了测试。结果表明,经热处理钢组织仍为马氏体,N-T(1050℃正火+755℃回火)、N2-T和N-N-T试验钢硬度分别为285HV、275HV和312HV,晶粒尺寸分别为8.8、11.7和8.0μm。N-N-T可以有效细化晶粒。中间等温热处理后,钢中MX相优先析出,消耗了过饱和马氏体中的碳,利于M_(23)C_(6)相尺寸和体积分数的降低,N2-T钢中M_(23)C_(6)尺寸由N-T钢的128 nm降低至80 nm,N-N-T钢降低至84 nm;N2-T钢中M_(23)C_(6)体积分数由N-T钢的0.0110%降低至0.0085%,N-N-T钢降低至0.0090%。N2-N由于随炉冷增加了保温时间,晶粒和MX相粗化,恶化了钢的性能。较小的晶粒尺寸和细小的M_(23)C_(6)和MX相是N-N-T试验钢获得优良力学性能的主要原因,其室温屈服强度为662 MPa,抗拉强度为787 MPa,伸长率为26.1%,DBTT为-91℃,室温冲击功为346 J。 展开更多
关键词 低活化钢 中间热处理 M_(23)C_(6) MX 力学性能
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低活化钢的氦离子辐照损伤行为 被引量:2
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作者 夏礼栋 霍晓杰 +3 位作者 张弛 高达利 吴长江 张师军 《金属热处理》 CAS CSCD 北大核心 2022年第7期211-216,共6页
利用氦离子辐照研究了不同辐照温度下低活化钢的辐照损伤行为,采用透射电镜和纳米压痕仪测量和表征了辐照引起的缺陷组织和硬化效应,并分析了两者之间的影响关系。结果表明,氦离子辐照造成的组织变化主要包括气泡和MC相的粗化。气泡在... 利用氦离子辐照研究了不同辐照温度下低活化钢的辐照损伤行为,采用透射电镜和纳米压痕仪测量和表征了辐照引起的缺陷组织和硬化效应,并分析了两者之间的影响关系。结果表明,氦离子辐照造成的组织变化主要包括气泡和MC相的粗化。气泡在晶界上发生聚集,辐照剂量越大,气泡密度越高;辐照温度越高,气泡尺寸越大、密度越低。辐照之后,低活化钢硬度提高,且辐照温度上升,硬化效应降低。辐照硬化值与缺陷组织的尺寸和密度相关,高密度的小尺寸气泡是氦离子辐照硬化的主要因素,辐照温度升高,气泡密度降低,辐照硬化减弱。 展开更多
关键词 低活化钢 氦离子辐照 缺陷组织 辐照硬化
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Effect of TaC Particles Dissolution on Grain Coarsening in Reduced Activation Steels
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作者 XIA Zhi-xin ZHANG Chi +3 位作者 HUANG Qun-ying LIU Shao-jun LI Zhao-dong YANG Zhi-gang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第9期47-52,共6页
The effect of TaC on grains and packets coarsening in the reduced activation ferritic/martensitic (RAFM) steels was investigated. It was found that the combined effect of the austenitizing temperature and heating ra... The effect of TaC on grains and packets coarsening in the reduced activation ferritic/martensitic (RAFM) steels was investigated. It was found that the combined effect of the austenitizing temperature and heating rate resulted in the heterogeneous austenite grain growth. When the austenitizing temperature was raised above 1 423 K, the TaC particles disappeared, and the homogenous grains abruptly increased. The thermodynamic model for dissolution of TaC particles during austenitizing was applied to interpret the results. 展开更多
关键词 reduced activation steel TaC precipitation diffusion thermodynamic model
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热处理对新型低活化钢组织及力学性能的影响
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作者 高云飞 曹磊 +1 位作者 邱国兴 禚学院 《金属热处理》 CAS CSCD 北大核心 2023年第12期79-86,共8页
以真空感应+电渣重熔制备的新型低活化钢为研究对象,研究正火和回火温度对微观组织和力学性能的影响。利用相变仪和Thermo-Calc软件对试验钢相变温度进行了测试和计算;利用金相显微镜、扫描电镜和透射电镜对试验钢显微组织和析出相进行... 以真空感应+电渣重熔制备的新型低活化钢为研究对象,研究正火和回火温度对微观组织和力学性能的影响。利用相变仪和Thermo-Calc软件对试验钢相变温度进行了测试和计算;利用金相显微镜、扫描电镜和透射电镜对试验钢显微组织和析出相进行了观察;利用显微硬度计、电子万能材料试验机和摆锤式冲击试验机对钢硬度、拉伸性能和冲击性能进行测试。结果表明,较低正火温度不能消除轧制带状组织,较高正火温度将造成晶粒粗化;回火后组织均为回火马氏体,755℃和790℃回火可避免Laves相的析出,随回火温度的升高,钢中M23C6和MX析出相发生粗化,碳化物的析出降低了碳的固溶强化作用;随回火温度的升高,钢的显微硬度、屈服强度和抗拉强度不断降低。在690~755℃回火区间内,钢伸长率和室温冲击吸收能量随回火温度的升高而增加,韧脆转变温度随回火温度的升高而降低。790℃回火钢伸长率和室温冲击吸收能量降低,韧脆转变温度升高;经1050℃×30 min正火+755℃×90 min回火,试验钢可获得最佳综合力学性能,细小的晶粒尺寸和弥散分布的纳米级碳化物是其优良力学性能的关键。 展开更多
关键词 低活化钢 正火 回火 析出相 拉伸性能 冲击性能
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温度对纯铁中间层连接低活化钢扩散行为的影响 被引量:1
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作者 陈永充 王均安 +3 位作者 何亚利 包喜荣 陈崇林 张朦 《上海金属》 CAS 2022年第2期15-23,共9页
采用Gleeble-3500热模拟试验机,在950~1100℃进行了低活化钢加纯铁中间层的扩散连接,通过对连接界面附近显微组织、元素分布和显微硬度的分析和测试,研究了温度对连接界面元素扩散行为的影响。结果表明:经不同温度扩散连接后,接头的显... 采用Gleeble-3500热模拟试验机,在950~1100℃进行了低活化钢加纯铁中间层的扩散连接,通过对连接界面附近显微组织、元素分布和显微硬度的分析和测试,研究了温度对连接界面元素扩散行为的影响。结果表明:经不同温度扩散连接后,接头的显微组织由母材的板条马氏体、连接界面处的Fe-Cr固溶体和中心层未发生扩散的纯铁3部分组成。连接界面处发生互扩散形成扩散层,扩散层的厚度随温度升高而增加;Cr元素在纯铁中间层的扩散符合菲克第二定律,扩散系数与温度的关系为D=1.43×10^(-7) exp(-210900/RT)。 展开更多
关键词 低活化钢 扩散连接 纯铁中间层 扩散行为
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Experimental and theoretical analysis of equilibrium segregation and radiation-induced segregation of Cr at grain boundariesin a reduced activation ferritic/martensitic(RAFM)steel 被引量:1
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作者 Li-dong Xia Hao Chen +1 位作者 Zhi-gang Yang Chi Zhang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2021年第4期445-452,共8页
Helium ion irradiation at 350℃was performed to study equilibrium segregation and radiation-induced segregation(RIS)of Cr at grain boundaries in reduced activation ferritic/martensitic steels.Cr concentration at grain... Helium ion irradiation at 350℃was performed to study equilibrium segregation and radiation-induced segregation(RIS)of Cr at grain boundaries in reduced activation ferritic/martensitic steels.Cr concentration at grain boundary was measured by scanning transmission electron microscopy with an energy-dispersive spectrometer.The measured Cr concentration at grain boundaries in heat treated zone was 11.7 and 12.8 wt.%in irradiated zone,respectively,which matched well to the calculated results from Mclean and modified Perk model.Equilibrium segregation and RIS of Cr mechanisms were theoretically analysed.The analysis indicates that as temperature rises,equilibrium Cr segregation decreases monotoni-cally,while RIS of Cr has a bell-shape profile,which increases first and then decreases.It is also shown that at low and high temperatures,equilibrium segregation of Cr is higher than that of RIS;at intermediate temperatures,equilibrium Cr segregation is lower than RIS. 展开更多
关键词 reduced activation ferritic/martensitic steel Equilibrium Cr segregation Radiation-induced segregation Grain boundary Rate theory Mclean equation
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高温时效对低活化钢微观组织及力学性能的影响
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作者 邱国兴 张红钊 +3 位作者 杨永坤 李小明 彭雷朕 曹磊 《材料热处理学报》 CAS CSCD 北大核心 2023年第8期115-122,共8页
采用光学显微镜、扫描电镜(SEM)、透射电镜(TEM)和力学性能测试等研究了经中间热处理的含钇和钛的低活化钢在550℃时效500、1250、2500、4000和5000 h后的组织和性能变化规律,并分析了微观组织变化对力学性能的影响。结果表明:时效过程... 采用光学显微镜、扫描电镜(SEM)、透射电镜(TEM)和力学性能测试等研究了经中间热处理的含钇和钛的低活化钢在550℃时效500、1250、2500、4000和5000 h后的组织和性能变化规律,并分析了微观组织变化对力学性能的影响。结果表明:时效过程中实验钢的组织保持为稳定的马氏体,晶粒发生粗化,M_(23)C_(6)和MX相的长大速率、屈服强度、抗拉强度和冲击性能逐渐降低并趋于稳定。时效时间增加至4000 h后,Laves相的粗化速度有所降低。当时效时间达到5000 h时,实验钢的晶粒尺寸为9.1μm,M_(23)C_(6)的长大速率为0.0072 nm/h,MX的长大速率为0.0004 nm/h,实验钢的室温屈服强度和抗拉强度分别为632和755 MPa,室温冲击吸收能量为307 J,韧脆转变温度为-64℃,实验钢在650℃时屈服强度和抗拉强度分别为313和337 MPa。晶粒粗化是实验钢冲击韧性降低的主要原因。 展开更多
关键词 低活化钢 高温时效 LAVES相 M_(23)C_(6) MX 力学性能
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Effect of thermal cycles on microstructure of reduced activation steel fabricated using laser melting deposition 被引量:1
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作者 Qian An Zhi-xin Xia +2 位作者 Chi Zhang Zhi-gang Yang Hao Chen 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2021年第3期316-326,共11页
Reduced activation steel was successfully fabricated by laser melting deposition employing a Gaussian and a ring-shaped laser.The microstructure evolution of the reduced activation steel was investigated using the sca... Reduced activation steel was successfully fabricated by laser melting deposition employing a Gaussian and a ring-shaped laser.The microstructure evolution of the reduced activation steel was investigated using the scanning electron microscope,transmission electron microscope and electron backscatter diffraction.The experimental results showed that the grains close to the substrate were smaller than the grains in the upper layers.Compared to those deposited using a Gaussian laser,the samples deposited using a ring-shaped laser showed a more homogeneous microstructure.Furthermore,a finite element analysis(FEA)model was applied to reveal the thermal history during laser melting deposition.The simulation results were well validated with the experimental results.FEA results indicate that the peak temperature increases and the cooling rate decreases,as the layer gets further from the substrate.Additionally,the temperature and the cooling rate resulting from the Gaussian laser model were higher at the midline of the samples and lower around the edges,whereas those of the ring-shaped laser model were consistent with both at the center and around the edges. 展开更多
关键词 Laser melting deposition reduced activation steel Microstructure evolution Thermal cycle Finite element analysis
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Unsteady state precipitation of M_(23)C_(6)carbides during thermal cycling in reduced activation steel manufactured by laser melting deposition
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作者 Ji-xin Hou Fu-lin Zhang +5 位作者 Zhi-xin Xia Yun-he Yu Hai-ying Fu Shu-hai Huang Qian An Chi Zhang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第3期557-568,共12页
The temperature field distribution and thermal history of Fe-9Cr2WVTa reduced activation steel prepared by laser melting deposition(LMD)have been calculated with Gaussian and Ring laser beams,and the nucleation and gr... The temperature field distribution and thermal history of Fe-9Cr2WVTa reduced activation steel prepared by laser melting deposition(LMD)have been calculated with Gaussian and Ring laser beams,and the nucleation and growth behaviors of M_(23)C_(6)precipitates in the 1st,7th and 19th layers have been calculated using the modified classical nucleation theory and Svoboda Fischer Fratzl Kozeschnik model.The energy distribution shows W-shape with Ring laser beam while it shows V-shape with Gaussian laser beam,which results in the more uniform M_(23)C_(6)size in the same layer with Ring laser beam.Precipitates in the bottom(i.e.,the 1st layer)have the minimum size and the size increases with the layer number with Gaussian and Ring laser beams.The temperature history,the instantaneous nucleation rate and the size evolution of M_(23)C_(6)have been systematically discussed.The results indicate that the nucleation,growth and re-dissolution of precipitates in reduced activation steel depend on the amount of energy absorbed in the thermal cycle during LMD.The continuous accumulation of energy during the thermal cycle leads to larger M_(23)C_(6)at the top area.The unsteady state precipitation dynamics of M_(23)C_(6)carbides during thermal cycling are consistent with the simulation results. 展开更多
关键词 Laser melting deposition reduced activation steel Unsteady state precipitation Heat source model
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Yield Stress Prediction Model of RAFM Steel Based on the Improved GDM-SA-SVR Algorithm
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作者 Sifan Long Ming Zhao Xinfu He 《Computers, Materials & Continua》 SCIE EI 2019年第3期727-760,共34页
With the development of society and the exhaustion of fossil energy,researcher need to identify new alternative energy sources.Nuclear energy is a very good choice,but the key to the successful application of nuclear ... With the development of society and the exhaustion of fossil energy,researcher need to identify new alternative energy sources.Nuclear energy is a very good choice,but the key to the successful application of nuclear technology is determined primarily by the behavior of nuclear materials in reactors.Therefore,we studied the radiation performance of the fusion material reduced activation ferritic/martensitic(RAFM)steel.The main novelty of this paper are the statistical analysis of RAFM steel data sets through related statistical analysis and the formula derivation of the gradient descent method(GDM)which combines the gradient descent search strategy of the Convex Optimization Theory to get the best value.Use GDM algorithm to upgrade the annealing stabilization process of simulated annealing algorithm.The yield stress performance of RAFM steel is successfully predicted by the hybrid model which is combined by simulated annealing(SA)with support vector machine(SVM)as the first time.The effect on yield stress by the main physical quantities such as irradiation temperature,irradiation dose and test temperature is also analyzed.The related prediction process is:first,we used the improved annealing algorithm to optimize the SVR model after training the SVR model on a training data set.Next,we established the yield stress prediction model of RAFM steel.The model can predict up to 96%of the data points with the prediction in the test set and the original data point in the 2range.The statistical test analysis shows that under the condition of confidence level=0.01,the calculation results of the regression effect significance analysis pass the T-test. 展开更多
关键词 Convex optimization theory simulated annealing algorithm reduced activation ferritic/martensitic steel support vector regression.
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