LIN Yijian HU Jian YOU Yunlong JING Chunyong YU Quanqin Shanghai Iron and Steel Research Institute
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Shanghai
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China LIN Yijian Measuring and Testing Centre
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Shanghai Iron and Steel Research Institute
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Shanghai 200940
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China
金属学报(英文版)
The formation of borides M_3B_2 M_2B_2 and M_(23)B_6 may be carried out from the melt-quenched Fe_(70)Cr_(18)Mo_2SiB_9 during 700—1150℃ annealing.As the temperature raising,the M_2B,the majority being Fe_2B.may be gradually replaced by Cr_2B via the co-existence between Fe_2B and Cr_2B.The Cr_2B may be formed by trans formation of Fe_2B through the atomic substitu- tion and structural adjustment.The thin slice of remaining Fe_2B is sandwiched between(100) faces of(Cr,Fe)_2B as stacking fault.The M_2B_2 is virtually composed of the Mo_(1+x)(Fe,Cr)_(2-x)B_2 where x(0≤x≤1)increases with the increase of temperature.
关键词:
FeCrMoSiB alloy
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null
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null
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null
TENG Feng'en WANG Yuming XU Yue Jilin University
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Changchun
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China
金属学报(英文版)
X-ray diffraction profiles of various deformed steel 1Cr18Ni9 through stepped scanning were obtained.By profile analysis,some structure parameters such as effective domain size D_(eff), dislocation density in domain,distribution parameterand bulk stored energy densiy (E/V),etc.,were obtained.The results were compared with those of TEM observation.The true domain sizes D_e are comparable,but the minimum and characteristics of width of stack- ing fault are different.This may be resulted from the large fluctuation in width of stacking fault.
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austenitic stainless steel
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null
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null
房菲
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黄健
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李静媛
上海金属
通过热模拟试验研究了不同试验温度下,氮质量分数分别为0.07％、0.34％、0.44％和0.72％的18Mn18CrN钢的断面收缩率和抗拉强度等力学性能.结果表明:(1)18Mn18CrN钢的断面收缩率随着试验温度的升高而增大,但当温度高于1 200℃时,略有下降;(2)氮含量增加,钢具有高塑性的温度区变窄,氮质量分数为0.72％的钢,其具有最佳力学性能的温度区缩小至1 150～1200℃;(3)随着试验温度的升高,18Mn18CrN钢的抗拉强度均呈线性下降的趋势,且氮含量越高,其高温抗拉强度对温度的变化越敏感;(4)氮含量增加,18Mn18CrN钢的断面收缩率呈“V”形趋势变化.
关键词:
18Mn18CrN钢
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氮含量
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高温塑性
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试验温度
GAO Hua CAO Weijie ZHOU Deqi WANG Ruizhen Shanghai University of Engineering Science
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Shanghai
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China
金属学报(英文版)
A series of mixed mode tests were carried out on 18-8 stainless steel in boiling 42% MgCl_2 solution.The results show that for any K_Ⅱ/K_Ⅰ ratio,the SCC direction coin- cides well with the crack tip maximum normal stress plane,while the SCC resistance of the material reduces as the ratio of K_Ⅱ/K_Ⅰ increases.The experimental results were discussed in the light of anode dissolving mechanism and the effect of mixed mode loading on crack tip stress and strain.It is concluded that for fracture analysis if mixed mode cracks were simply taken into account as mode Ⅰ cracks,and only mode Ⅰ testing results as mode Ⅰ fracture criter- ion were employed,it may not be safe.
关键词:
18-8 stainless steel
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null
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null
M. Guan
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J. L. song and H. G. Guo Taiyuan Heavy Machinery Institute
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Taiyuan 030024
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China
金属学报(英文版)
In the hot forming of Mn18Cr18N steel, such problems as easy cracking, difficult controlling of forming paramenters often occur. In this paper,the variation rule of the plasticity of the steel, the starting mechanism of micro-crack and its generating characteristics were studied with the combination of thermodynamic simulation test, micro-simulation and FEM, the related data of microstructure change and hot forming parameters were produced. The hot forming process of 600MW generator retaining ring was analyzed as an example.
关键词:
Mn18Cr18N
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null
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null
Acta Materialia
An analytical relationship between the ratio of hardness to reduced modulus H/E-r and the geometry of a residual indent is established based on the theories of depth-sensing indentation. Various material parameters, including elastic parameters, recovery deformation and energy-dissipation capacity, are uniquely determined by the value of H/E-r, so that they can be estimated from a residual indent trail. Thus, we are able to know what has happened in the material simply by analyzing or comparing residual trails on the material. The validity of this method has been confirmed by analyzing residual Vickers indents on quasi-plastic ceramic and brittle glass. In addition, it is demonstrated that the geometric constant epsilon in traditional nanoindentation theories is related to the proportional factor eta through the exponent of unloading curve m, i.e., epsilon = m (.) eta, where eta is defined by h(s) = eta (.) (h(m) - h(f)). (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
关键词:
residual indent;Vickers indenter;property prediction;H/E-r ratio;depth-sensing indentation;instrumented indentation;mechanical-properties;nanoindentation;modulus;hardness;deformation;films;load;substrate
陈慧琴
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刘建生
金属学报
运用热耦合刚粘塑性有限元微观模拟技术, 对Ｍｎ１８Ｃｒ１８Ｎ钢护环扩挤复合热成形和冷却过程进行了计算机模拟. 得到了热力参数的分布状况和内部晶粒度变化的规律. 当空冷约２１０ｓ时护环内晶粒可达细匀化. 这为实现环的控制锻造与控制冷却, 进而控制产品质量提供了理论依据.
关键词:
Mn18Cr18N钢
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null
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null
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null
邱巨峰
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程万荣
金属学报
<正> Cr 18 Ni 18 Si 2钢经热处理后的低温冲击断口,其中加稀土的为穿晶断口,而未加稀土的为混合型断口。 试验用钢用高频感应炉冶炼,锭重20kg,锻成15×15mm方棒,再加工成冲击试样。其化学成分如下。稀土的加入是将一号混合稀土合金缚在钢棒上插入熔池。
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