YANG Ying
,
YAN Qing-zhi
,
MA Rong
,
GE Chang-chun
钢铁研究学报(英文版)
Ferritic/martensitic (F/M) steels have been recommended as one of the candidate materials for supercritical water cooled reactor (SCWR) in-core components use for its high thermal conductivity, low thermal expansion coefficient and inherently good dimensional stability under irradiation condition in comparison to austenitic steel. CNS-Ⅱ F/M steel which has good mechanical properties was one of the 9-12Cr F/M steels designed for SCWR in the previous work. In this study a modified CNS-Ⅱ F/M steel was used and it′s ultimate tensile strength was 925 MPa at room temperature and 483 MPa at 600 ℃ after optimizing heat treatment parameter. The ductile to brittle transition temperature of modified CNS-Ⅱ F/M steel is -55 ℃. Those are at the same level or even higher than that of CNS-Ⅱ and some commercial F/M steels nominated for SCWR in-core component use. The transmission electron microscope (TEM) results showed that the mechanical properties of the tempered martensite was closely related to the decomposition stage of the martensite.
关键词:
supercritical water reactor
,
ferritic/martensitic steel
,
cladding material
Dongqing LI
,
Jun TAO
,
Qingguo Meng
,
Hongyuan FANG
材料科学技术（英）
By means of a newly developed non-contact detecting method, electronic speckle pattern interferometry (ESPI), a method of determining material property data during welding is studied. A TIG fixed-point welding process is modeled in which some achievements of simulation, such as the effect of welding pool on temperature field and nonlinear relation between convection coefficient and temperature, are all considered. In addition, by taking into account effect of heating rate, the workpiece is divided into near-weld zone and far-weld zone, which will be treated with different property values. When the displacement field computed with original property data is compared and matched with the experimental displacement field, which is measured by ESPI, these original data are adjusted properly. A group of raw properties are obtained and are corrected by statistical regression before they enter the simulation process again. By such a loop of “simulation-comparison-modification”, a set of property data that best satisfy the real condition are achieved finally. In such a way, a new method for measuring material properties during welding is found.
关键词:
Material properties
,
null
,
null
,
null
Jingchuan ZHU
,
Zhongda YIN and Zhonghong LAI(Dept. of Metals and Technology
,
Harbin Institute of Technology
,
Harbin
,
150001. China)
材料科学技术（英）
The fabrication. microstructure and mechanical properties of ZrO2-Ni functionally gradient materials (FGM ) have been studied. FGM as well as non-FG M of ZrO2-Ni system was developed by powder metallurgical process. X-ray diffractometer (XRD ). electron probe microanalyzer (EPMA), scanning electron microscope (SEM ) and optical microscope were employed to investigate the crystalline phases. chemical composition and microstructure Experimental results demonstrate that the composition and microstructure of ZrO2-Ni FGM have the expected gradient distribution. There are no distinct interfaces in the FGM due to the gradient change of components. that is, the constituents are continuous in microstructure everywhere. Moreover, Vickers hardness and flexural strength were measured for the common composites as a function of composition. It is made clear that the mechanical properties of the FGM vary corresponding to the constitutional changes as well
关键词:
SONG Ren-bo
,
XIANG Jian-ying
,
HOU Dong-po
钢铁研究学报(英文版)
A comparative study on mechanical properties and microstructure of 316L austenitic stainless steel between solution treated specimen and hot rolled specimen was conducted. After a specimen was subjected to solution treatment at 1050 ℃ for 6 min, its mechanical properties were determined through tensile and hardness tests. Based on the true stress vs true strain and engineering stress vs engineering strain flow curves, the work hardening rate has been explored. The results show that the solution treated specimen has an excellent combination of strength and elongation, and that this steel is easy to work-hardening during deformation. Optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffraction examinations were conducted, these reveal that twins in 316L austenitic stainless steel can be divided into suspended twin and transgranular twin which have different formation mechanisms in growth, and that the deformation induced martensite nucleated and grown in the shear band intersections can be observed, and that the fracture surfaces are mainly composed of dimples and exhibit a tough fracture character.
关键词:
316L
,
mechanical property
,
twin
,
martensite
,
fracture morphology
Author S.T. TU
,
J.M. Gong and X. Ling Nanjing University of Chemical Technology
,
Nanjing 210009
,
ChinaManuscript received 18 October 1998
金属学报(英文版)
In order to interpret the test results of crossweld specimens for application in practical welded components, the present paper studies the high temperature behavior of laboratory cross weld specimens in terms of the uniaxial material tests and numerical simulations. It is found that the crossweld specimen may be used for the high temperature strength assessment, but can hardly be used for life assessment of the practical welded components, which depends on the loading conditions of the components.
关键词:
high temperature
,
null
,
null
,
null
,
null
Z.Q. Hu
,
W.R.Sun and S.R. Guo(Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China Manuscript received 26 August 1996)
金属学报(英文版)
The effects of the trace elements, P, S and Si,on the solidification, segregation,microstructure and mechanical properties of GH761 and In718 alloys were studied.It was found that the segregation of the P,S and Si can be greatly aggravated or relieved by the precipitation taking place during the solidification. In the heat treated state,P enhances the intergranular precipitation in the GH761 alloy.The refinement of P in In718 alloy causes the appearance of a film-like δphase.Si increases the intergranular precipitation of the M_6C and the Laves Phase in the In718 alloy.P, S and Si play diverse roles in the tensile and the stress rupture properties of the GH761 and In718 alloys. The most striking effect is that P significantly prolongs the stress rupture lives of the GH761 and In718 alloys in a wide range of 0.00050.015 wt% .The mechanisms by which P,S and Si influence the superalloys are discussed in the text.
关键词:
: superalloy
,
null
,
null
,
null
林海
,
许杰
,
范白涛
,
张羽臣
,
王桂萍
,
霍宏博
,
殷启帅
表面技术
doi:10.16490/j.cnki.issn.1001-3660.2016.05.014
目的：研究L80钢在CO2/H2S环境中的力学特性。方法利用微机控制慢应变速率拉伸试验机，对特定腐蚀条件下的L80钢试样进行拉伸实验，分析各因素对L80钢力学特性的影响变化规律。结果在CO2/H2S环境中，随着含水率的增加，L80钢的屈服强度、抗拉强度、延伸率均下降，L80钢拉伸曲线出现劣化。随预拉应力的增大，L80钢的屈服强度变化不明显，而抗拉强度和延伸率降低，当预拉应力超过0.8σs时，L80钢的腐蚀速率显著增加，表现出较强的应力腐蚀敏感性；随着H2S分压的增加， L80钢的力学性能发生劣化，表现出氢脆敏感性，而受CO2分压的影响不明显；温度升高导致L80钢的拉伸曲线出现了轻度劣化，延伸率和屈服区宽度小幅降低，但抗拉强度变化不大。结论 L80钢在CO2/H2S环境中的力学特性受温度、CO2分压影响程度小。含水率和预拉应力的增大降低了L80钢的力学韧性，预拉应力的存在使L80腐蚀速率加快，缩短了耐腐蚀寿命。L80钢的力学性能对于H2S分压较对CO2分压更为敏感，试样的断裂是机械拉力和应力腐蚀共同作用的结果。
关键词:
L80钢
,
CO2腐蚀
,
H2S腐蚀
,
力学特性
,
腐蚀速率
,
应力腐蚀
赵景茂
,
魏辉荣
,
张娇娇
,
熊金平
,
唐聿明
,
左禹
腐蚀科学与防护技术
运用BP人工神经网络技术建立了预测L360钢在H2S/CO2环境中腐蚀的模型,神经网络拓扑结构为5-4-1, 网络模型训练成功以后,应用它预测L360钢在H2S/CO2中的腐蚀速度. 结果表明,人工神经网络模型预测的结果与实验数据相当符合, 误差在14%以内.由此可见,BP神经网络模型可以作为预测H2S/CO2环境致集输管线腐蚀速率的工具.
关键词:
L360钢
,
H2S/CO2 corrosion
,
BP artifical neural network
,
corrosion rate
林海
,
许杰
,
幸雪松
,
范白涛
,
杨进
,
王晓鹏
表面技术
doi:10.16490/j.cnki.issn.1001-3660.2016.05.013
目的：研究L80油管在CO2/H2S环境中的腐蚀行为。方法利用扫描电镜（SEM）、EDAX能谱分析L80油管内壁腐蚀产物形貌特征和化学组成，采用高温高压反应釜，以实际油水分离的水样为腐蚀介质进行模拟实验，研究原油含水率、CO2/H2S 分压和温度对 L80油管腐蚀速率的影响规律。结果在CO2/H2S环境中，L80油管内壁呈现明显的局部腐蚀特征，部分表面点蚀坑深度超过100μm，形成FeS、FeCO3等腐蚀产物。随着含水率的增加，L80油管腐蚀速率逐渐增大，含水率为30%时的腐蚀速率为0.0377 mm/a，含水率为100%时的腐蚀速率为0.0952 mm/a。CO2分压不变时，随着 H2S分压的增加，L80钢的腐蚀速率增大，H2S分压为0.04 MPa时的腐蚀速率为0.0377 mm/a，H2S分压为0.3 MPa时的腐蚀速率为0.0952 mm/a；H2S分压不变时，随着CO2分压的增大，L80钢腐蚀速率变化不明显且腐蚀速率较小。随着温度的升高，腐蚀速率先以较大幅度增大，再以较小幅度减小，从40℃增加至100℃时，腐蚀速率由0.0083 mm/a升至0.1264 mm/a，100℃左右时的腐蚀速率最大，120℃对应的腐蚀速率为0.106 mm/a。结论 L80油管在CO2/H2S环境中以均匀腐蚀和局部点蚀为主。L80油管腐蚀速率对H2S分压比CO2分压更敏感，CO2分压增大促使具有良好保护性的FeCO3保护膜的形成，降低了腐蚀速率。温度升高至一定范围，导致碳酸盐等难溶性盐溶解度降低，并覆盖在钢表面形成保护层，从而使腐蚀速率下降。
关键词:
L80油管钢
,
CO2/H2S腐蚀
,
腐蚀产物
,
腐蚀速率
,
腐蚀形貌
,
影响因素
