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高碳钢线材组织性能的研究 总被引:1,自引:1,他引:0
介绍了武汉钢铁股份有限公司高线车间的主要工艺设备概况及生产高碳钢线材(硬线)存在的性能不合问题。阐述了在硬线生产过程中建立奥氏体再结晶模型、奥氏体相变模型、组织模型和力学性能模型的基本方法,以及开展线材组织性能预报研究对生产工艺优化的意义。武钢在合作研究的性能预报项目中,其预报结果与实测结果十分吻合。 相似文献
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采用热模拟法研究了2205DSS焊接HAZ的组织与性能,探讨了冷却时间对模拟HAZ冲击韧性的影响规律。结果表明:冷却时间对组织及性能有很大的影响,随冷却时间的延长,铁素体含量减少,奥氏体含量增加,冲击韧性增大:随冷却时间延长,模拟组织显微硬度降低,而且模拟组织中铁素体的硬度低于奥氏体的硬度:固定冷却时间t8/5时,随冷却时间t12/8的增加,冲击韧性提高:固定冷却时间t12/8时,随冷却时间t8/5的增加,冲击韧性降低。 相似文献
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选取传统高强度双相钢HC420/780DPD+Z和与其化学成分相同、组织存在一定量残余奥氏体差异的HC440/780DHD+Z为研究对象,研究了残余奥氏体对高强度双相钢断裂失效性能的影响。设计了5种表征不同断裂失效状态的试样,测试获得各试样的临界断裂应变和力-位移曲线;采用有限元法搭建了试样模型,并对比了试验和仿真关键参数误差,验证了模型的准确性。通过模型获取了各试样断裂单元的应力三轴度和临界断裂应变;基于MMC断裂失效模型拟合获得断裂失效曲线;采用90°V型弯曲试验和仿真对比分析验证了断裂失效曲线的准确性。结果表明,残余奥氏体组织加入后,高强度双相钢的抗拉强度基本保持不变,断后伸长率、强塑积和应变硬化指数明显提升;断裂失效性能明显提升,相同应力三轴度的极限断裂失效应变明显提高;90°V型弯曲模型获取的临界塑性应变与断裂失效曲线提取的数值一致,表明所获得的断裂失效曲线是可靠的;在基体组织中引入一定量的残余奥氏体组织有助于提升高强度双相钢碰撞过程中的承载吸能特性。 相似文献
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高锰钢中奥氏体的加工硬化机理 总被引:8,自引:0,他引:8
对铸造型的高锰钢(ZGMnl3),水韧处理获得单一奥氏体耐磨钢的应力应变和残体硬度作了分析讨论,说明高锰钢奥氏体具有相当高的加工硬化度,在室温下权限变形后,共硬度远未达到峰值,因此,奥氏体高锰钢的加工硬化特性是由奥氏体本身强化作用影响产生的。同时迁就高锰钢的主要化学成分对组织及性能的影响,大型高锰钢件的制造中的问题作了简要介绍。 相似文献
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介绍了ISO 2892:2007标准中规定的奥氏体铸铁材料的基本性能,奥氏体铸铁具有优良的耐热性、耐蚀性、低温抗冲击性、抗氧化性、低的热膨胀性能和无磁性的优点。奥氏体铸铁基体组织为稳定的奥氏体组织,不能通过热处理来改善其性能,但通过热处理可以去除残余应力和高温稳定化,从而保证铸件在机械加工过程中不发生变形,确保其尺寸稳定性。奥氏体铸铁的性能取决于其化学成分,特别是铬、锰、钼和硅含量。奥氏体铸铁具有一定的断面敏感性,与灰铸铁和球墨铸铁断面敏感性的表现有所不同。 相似文献
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为准确描述40CrMnMoA合金钢的奥氏体晶粒长大行为,借助Gleeble-1500D型热模拟机对40CrMnMoA合金钢进行了保温试验,温度为900~1150℃,时间为10~2000 s。基于试验结果,通过非线性回归建立了40CrMnMoA合金钢Burke-Turnbull奥氏体晶粒长大模型,构建了基于Level Set方法的40CrMnMoA合金钢奥氏体晶粒长大的介观尺度有限元模型并进行计算。结果表明:保温温度与保温时间对40CrMnMoA合金钢的晶粒长大行为均具有较大的影响。40CrMnMoA合金钢的奥氏体平均晶粒直径随保温时间的延长呈抛物线增长。所建立的Burke-Turnbull晶粒长大动力学模型具有较高的精度,试验值与计算值相关系数(R)为0.9932。40CrMnMoA合金钢奥氏体再结晶晶粒长大激活能(Qm)为142845.37 J/mol。通过对比仿真计算与试验所得的晶粒组织,验证了本文所建有限元模型可有效地预测40CrMnMoA合金钢的奥氏体晶粒长大演变过程。 相似文献
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介绍了无碳化物贝氏体耐磨铸钢的合金化设计,研究了铸造无碳化物贝氏体耐磨钢热处理的组织和性能.铸造无碳化物耐磨钢正火低温回火热处理组织由贝氏体铁素体和奥氏体组成,属于非典型贝氏体或无碳化物贝氏体或奥氏体-贝氏体复相组织,淬火低温回火热处理组织由马氏体和残余奥氏体组成,属于马氏体-奥氏体复相组织.结果表明:铸造无碳化物贝氏体耐磨钢正火或淬火后低温回火,材料具有高的强度、高的韧性和高的耐磨性,低碳铸造无碳化物贝氏体耐磨钢具有良好的焊接性能.并介绍了铸造无碳化物贝氏体耐磨钢在矿山机械方面的应用. 相似文献
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MODELINGOFTHEPROCESSOFCOMPOSITEELECTRODEPOSITION¥XieYan;HuWenbin;LuoShoufu;GuMingyuan(StateKeyLaboratoryofMMCS,ShanghaiJiaoTo... 相似文献
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J.Zhang Metallurgical Engineering School University of Science Technology Beijing Beijing China 《金属学报(英文版)》2001,14(5):368-374
1. IntroductionThe thermodynamic properties of binary metallic melts have been c1early illustrated inRefs.[1-5]. Further work is to formulate calculating model8 of thermodynamic propertiesfor melts consisting of more than three components, especially for multicomponent meltsinvolving different kinds of binary metallic melts with sufficient application of thermody-namic properties of binary systems. The goal of this paper is to formulate the calculatingmodel of mass action concentrations for te… 相似文献
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RESEARCH ON THE SELECTION OF FRICTION MODELS IN THE FINITE ELEMENT SIMULATION OF WARM EXTRUSION 总被引:1,自引:0,他引:1
During the process of finite element simulation of precision warm forging, the selection of friction models has a direct effect on the precision accuracy of finite element simulation results. Among all the factors which influence the selection of friction models, the distribution rule of normal stress at the tool-workpiece interface is a key one. To find out the distribution rule of normal stress at the tool-workpiece interface, this paper has made a systematic research on three typical plastic deformation processes: forward extrusion, backward extrusion, and lateral extrusion by a method of finite element simulation. Then on the base of synthesizing and correcting traditional friction models, a new general friction model which is fit for warm extrusion is developed at last. 相似文献
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H. Tian J. Wang W.P. Dong J. Chen Z. Zhao G.M. Wu 《金属学报(英文版)》2005,18(5):627-634
Traditionally a rotary forging process is a kind of metal forming method where a conic upper die, whose axis is deviated an angle from the axis of machine, forges a billet continuously and partially to finish the whole deformation. For the rotary forging process simulation, more researches were focused on simulating the simple stage forming process with axisymmetric part geometry. Whereas in this paper, the upper die is not cone-shaped, and the billet is non-axisymmetric. So the movement of the punch is much more complicated than ever. The 3D FEM simulation models for the preforming & final forming processes are set up aider carefully studying the complicated movement pattern. Deform-3D is used to simulate the material flow, and the boundary nodal resisting forces calculated by the final stage process simulation is used to analyze the final forming die strength. The CAE analysis of the die shows that the design of the final forming die is not reasonable with lower pre-stress which is easy to crack at the critical corners. An optimum die design is also provided with higher pre-stress, and verified by CAE analysis. 相似文献
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针对粘合剂种类、Zn粒形状和涂层厚度的协同作用,采用电化学阻抗谱(EIS)研究了富Zn涂层在3.5%NaCl溶液中的电化学行为.富Zn涂层的EIS谱有两个时间常数,其中,锌的电子转移反应发生在低频段,而高频段则体现聚合物和Zn表面氧化层的介电性质.根据等效电路及其元件参数解释了钢铁/富Zn涂层/盐水体系的EIS测量结果.实验结果表明,鳞片锌消耗速度太快以至于鳞片富Zn涂层在相对较短的时间内就失去了阴极保护作用,随后形成了稍微致密的屏蔽阻挡层。 相似文献
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LI Zheng LIU Honglin CHENG Zhaonian CHEN Nianyi Shanghai Institute of Metallurgy Academia Sinica Shanghai ChinaZHOU Jiaju Institute of Chemical Metallurgy Academia Sinica Beijing China CHEN Nianyi Professor Shanghai Institute of Metallurgy Academia Sinica Shanghai China 《金属学报(英文版)》1992,5(7):74-76
The formability of complex flourides has been studied by chemical bond parameter-patternrecognition method. In a multi-dimensional space spanned by ionic radius, ionicpolarizability, electronegativity and ionic charge of the metal elements, the binary complexflouride-forming systems and binary flouride systems without complex flouride formation distributein different regions with a clear-cut boundary. The mathematical models obtained areuseful for new complex flouride predicton. 相似文献