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金属学报  2016, Vol. 52 Issue (10): 1207-1221    DOI: 10.11900/0412.1961.2016.00320
  本期目录 | 过刊浏览 |
核用新型耐高温、抗辐照、耐液态金属腐蚀结构材料——SIMP钢的研究进展*
杨柯1(),严伟1,王志光2,单以银1,石全强1,史显波1,王威1
1 中国科学院金属研究所, 沈阳 110016
2 中国科学院近代物理研究所, 兰州 730000
DEVELOPMENT OF A NOVEL STRUCTURAL MATERIAL (SIMP STEEL) FOR NUCLEAR EQUIPMENT WITH BALANCED RESIS-TANCES TO HIGH TEMPERATURE, RADIATION AND LIQUID METAL CORROSION
Ke YANG1(),Wei YAN1,Zhiguang WANG2,Yiyin SHAN1,Quanqiang SHI1,Xianbo SHI1,Wei WANG1
1 Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
2 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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摘要: 

加速器驱动次临界(accelerator driven subcritical system, ADS)系统由加速器、散裂靶、反应堆3部分组成, 被认为是安全处理核废料最具前景的技术方案. 其中, 散裂靶用结构材料需要同时具有耐高温、抗辐照、抗液态金属腐蚀等性能. 针对这一挑战研发了新型核用(9%~12%)Cr马氏体耐热钢——SIMP钢. 通过制衡(9%~12%)Cr马氏体耐热钢中C, Cr, Si等元素含量对耐高温、抗辐照、抗液态金属腐蚀性能的影响, 获得了SIMP钢优化的化学成分, 极好地平衡了SIMP钢耐高温、抗辐照、抗液态金属腐蚀3方面性能. 对1 t和5 t SIMP钢各项性能进行测试, 结果表明, SIMP钢是ADS系统中散裂靶的首选结构材料.

关键词 加速器驱动次临界(ADS)系统核结构用钢耐热辐照液态金属腐蚀    
Abstract

Accelerator driven subcritical (ADS) system has been recognized to be the most promising technology for safely treating the nuclear wastes by now. In China, ADS system has achieved great progress in both fundamental research and engineering practice. This system is composed of three parts, which are accelerator, spallation target and reactor. The biggest challenge exists in the structural material for the spallation target is to possess not only good heat-resistance and radiation resistance but also a resistance to liquid metal corrosion. A novel martensitic heat-resistant steel, SIMP steel, has been developed against this challenge. By negotiating the effects of the contents of those important elements such as C, Cr and Si in the (9%~12%)Cr martensitic heat-resistant steel on heat resistance, radiation resistance, and liquid metal corrosion resistance, an optimized chemical composition was obtained for SIMP steel and a good balance was reached among these three properties. The test results conducted on 1 t and 5 t grade SIMP steels showed that this novel steel is much potential as a candidate structural material for the spallation target in ADS system.

Key wordsADS system    steel for nuclear structure    heat-resistant    radiation    liquid metal corrosion
收稿日期: 2016-07-20      出版日期: 2016-08-29
:     
基金资助:* 中国科学院战略先导专项项目XDA03010301和XDA03010302资助

引用本文:

杨柯, 严伟, 王志光, 单以银, 石全强, 史显波, 王威. 核用新型耐高温、抗辐照、耐液态金属腐蚀结构材料——SIMP钢的研究进展*[J]. 金属学报, 2016, 52(10): 1207-1221.
Ke YANG, Wei YAN, Zhiguang WANG, Yiyin SHAN, Quanqiang SHI, Xianbo SHI, Wei WANG. DEVELOPMENT OF A NOVEL STRUCTURAL MATERIAL (SIMP STEEL) FOR NUCLEAR EQUIPMENT WITH BALANCED RESIS-TANCES TO HIGH TEMPERATURE, RADIATION AND LIQUID METAL CORROSION. Acta Metall Sin, 2016, 52(10): 1207-1221.

链接本文:

http://www.ams.org.cn/CN/10.11900/0412.1961.2016.00320      或      http://www.ams.org.cn/CN/Y2016/V52/I10/1207

图1  SIMP钢的成分设计思路
图2  不同规模SIMP钢铸锭
Steel C Si Cr Mn W Ta V S P Fe
1 t 0.22 1.22 10.24 0.52 1.45 0.12 0.18 0.0043 0.0040 Bal.
5 t 0.20 1.22 10.54 0.45 1.26 0.15 0.20 0.0030 0.0030 Bal.
表1  1 t级和5 t级SIMP钢的化学成分
5 t steel Ni Mo Ti Nb Al Co
Top of ingot
Bottom of ingot
0.0050 0.0008 0.003 0.0001 0.0050 0.002
0.0049 0.0005 0.003 0.0002 0.0050 0.001
表2  5 t级SIMP钢中的活化元素含量
图3  热处理态SIMP钢中的马氏体组织形貌的OM和TEM像
Steel Temperature
Yield strength MPa Tensile strength
MPa
Elongation
%
Reduction of area / % Impact toughness
J
1 t SIMP RT 582 825 23.5 65.0 132
600 267 355 44.0 - -
650 182 269 34.2 - -
5 t Up RT 613 833 20.5 64.3 109
SIMP 600 292 350 46.7 - -
650 218 273 34.5 - -
Middle RT 588 814 19.5 63.5 116
600 298 352 49.2 - -
650 220 275 38.6 - -
Down RT 598 823 21.7 63.3 111
600 305 360 39.8 - -
650 222 275 41.5 - -
T91 RT 521 699 24.0 74.0 82
600 281 344 42.0 95.0 -
650 177 272 39.0 98.0 -
表3  1 t级和5 t级SIMP钢及T91钢的常规力学性能
图4  1 t级SIMP钢与T91钢的持久性能对比
图5  5 t级SIMP钢与T91钢的持久性能对比
图6  1 t级SIMP钢650 ℃时效组织的SEM像
图7  SIMP钢和T91钢在700 ℃时的氧化增重及氧化增重速率
图8  SIMP钢与T91钢在800 ℃时的氧化增重及氧化增重速率
图9  SIMP钢与T91钢在700 ℃空气中氧化500 h后的氧化膜截面形貌的SEM像
图10  SIMP钢与T91钢在700 ℃空气氧化500 h后生成的氧化膜的XRD谱
图11  SIMP钢与T91钢在600 ℃的静态饱和氧液态Pb-Bi共晶(LBE)合金中腐蚀100, 500和1000 h后的氧化膜截面形貌的SEM像
图12  SIMP钢和T91钢在600 ℃静态饱和氧液态LBE合金中氧化膜厚度和扩散层厚度
图13  SIMP钢和T91钢在静态饱和氧液态LBE合金中腐蚀1000 h后氧化膜的EPMA元素分布
图14  SIMP钢和T91钢在600 ℃静态饱和氧液态LBE合金中腐蚀1000 h后内层Fe-Cr尖晶石的EPMA元素分布
图15  氧化膜与钢基体之间结合力的测试
图16  SIMP钢和T91钢在600 ℃静态饱和氧液态LBE合金中腐蚀不同时间后的室温拉伸性能
图17  SIMP钢和T91钢在600 ℃液态LBE合金中腐蚀不同时间后在600 ℃高温拉伸性能
Steel Original 300 h 500 h 1000 h 2000 h
T91 4.00 4.05 4.09 4.13 4.120
SIMP 4.00 4.05 4.08 4.14 4.115
表4  接触液态LBE不同时间后试样的平行段直径尺寸变化
图18  热处理态SIMP钢在300 ℃的液态LBE中的拉伸性能
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