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Surface Temperature Change of U75V 60 kg/m Heavy Rail During Heat Treatment

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Journal of Iron and Steel Research International 2013年第2期20卷 33-37,67页

作者： KANG Hao WU Di zhao xian-ming State Key Laboratory of Rolling and Automation Northeastern University

The U75V 60 kg/m heavy rail samples were heated to 900 ℃ in a resistance furnace for a fixed duration of 50 min. Under this condition, the samples were austenitized totally. Then, the samples were dragged out of furnace and cooled for 25 s in the open air. After that, the samples entered into the air spraying channel, and were cooled from the top and both sides by compressed air. During this period, main technical parameters were changed such as the distance between spray nozzles and surface of rail head, air pressure, air spraying time and air temperature. So under laboratory condition, optimal heat-treating parameters of U75V 60 kg/m heavy rail were determined as the distance between spray nozzles and surface of rail head of 15 mm, air pressure of 0.26 MPa, cooling time of 80 s, and air temperature of 28 ℃. The surface temperature at different positions of heavy rail was measured before and after heat treatment, and the temperature changing law was determined. The self tempering occurred on the surface of rail head after heat treatment, and the tempering temperature became the largest （about 3 min） after heat treatment, separately 528, 524 and 536 ℃ at the center, top fillet and bottom fillet of rail head. The heavy rail was cooled in open air after heat treatment; during this period, the temperature gap on the surface of heavy rail became smaller and smaller, and was reduced to zero when being cooled for 20 min.

关键词： temperature change heavy rail heat treatment

Modeling of Austenite Decomposition in Low Si-Mn TRIP Steel During Cooling

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Journal of Iron and Steel Research International 2008年第6期15卷 68-71页

作者： ZHU Li-juan WU Di zhao xian-ming College of Materials Science and Engineering Jilin University Changchun 130025 Jilin China The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

Transformation behavior in low carbon Si Mn TRIP steel was investigated by means of microstructural ob servation and computer modelling. A transformation model in which transformation is controlled by carbon diffusion was suggested, which well described the volume fractional change of ferrite, pearlite, and bainite during continuous cooling. The influence of Si content and austenite grain size was thoroughly investigated. The calculated results indicated that Si retards pearlite transformation, accelerates polygonal ferrite transformation, refines the austenite grain, and increases the ferrite transformation rate.

关键词： TRIP steel transformation incubation time ferrite bainite pearlite

Effect of Silicon Content on Thermodynamics of Austenite Decomposition in C-Si-Mn TRIP Steels

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Journal of Iron and Steel Research International 2006年第3期13卷 57-60,73页

作者： ZHU Li-juan WU Di zhao xian-ming State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Some numerical models such as central atoms model （CAM） and superelement model were used to simulate the thermodynamics of austenite decomposition in the Fe-C-Mn-Si TRIP （transformation induced plasticity） steels. Thermodynamic calculations were carried out under a para-equilibrium （PE） condition. The results show that certain silicon content can accelerate the polygonal ferritic transformation and increase the volume fraction and stability of retained austenite by retarding the precipitation of carbides during the bainitic transformation.

关键词： central atoms model superelement model para-equilibrium austenite decomposition TRIP steel

Explicit Dynamic FEM Analysis of Multipass Vertical-Horizontal Rolling

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Journal of Iron and Steel Research International 2006年第3期13卷 26-30页

作者： YU Hai-liang LIU xiang-hua zhao xian-ming WU Di Y. Kusaba State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Sumitomo Metal Industries Ltd Fuso-Cho 660 Amagasaki Japan

Three passes of plate rolling during vertical-horizontal rolling process are simulated with explicit dynamic finite element method and updating geometric method. The equivalent strain and stress fields, and shape change at the head and tail of slab during rolling are obtained. The calculated result of the shape at the head and tail of slab is in good agreement with the measured one. The explicit dynamic finite element method and updating geometric method can be used effectively to analyze the multipass vertical-horizontal （V-H） rolling process.

关键词： V-H rolling multipass equivalent stress strain slab shape

Effect of Controlled Cooling on Microstructure and Mechanical Properties of H-Beam

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Journal of Iron and Steel Research International 2013年第8期20卷 60-65页

作者： GUO Fei zhao xian-ming WANG Li-na WU Di WANG Guo-dong NING Zhong-liang State Key Laboratory of Rolling and Automation Northeastern University Fushun New Iron and Steel Company Ltd.

Based on ANSYS, an analytical model was established for H beam during controlled cooling. The tempera-ture fields during controlled cooling and air cooling were analyzed and the microstructure and mechanical properties for different parts of H-beam were discussed in detail. After the H-beam was controlled cooled for 4.5 s, its mean surface temperature decreased from 850 to 460 ℃, and the lowest and the highest temperatures were measured at edge of flange and at R corner, respectively. Whereas, for the H-beam air cooled for 30 s, the mean temperature at R corner and web was 700 and 540 ℃, respectively. The microstructures for different parts of H-beam consisted of ferrite and pearlite, and the grain size at R corner was coarser than those at flange and web. The difference of yield and tensile strengths of web, flange and R corner was within 30 MPa, and the elongation was similar. The changes of microstructure were in good agreement with that of temperature field. In addition, the results show that the uni formity of microstructure and mechanical properties can be improved by increasing water flow rate at R corner.

关键词： H-beam controlled cooling air cooling temperature field microstructure mechanical property

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赵先明辨治甲状腺癌术后的经验

中医肿瘤学杂志 2023年第1期5卷 48-52页

作者：黎颖娴段绍渊周淑怡赵先明广州中医药大学第一临床医学院广东广州510405 广州中医药大学第一附属医院二外科广东广州510405

甲状腺癌术后部分患者可出现咽部异物感、神疲乏力、食少纳呆、失眠多梦、心慌盗汗等不适症状,影响患者的日常生活,降低生活质量。赵先明认为甲状腺癌术后多本虚标实、虚实夹杂,常见证型为气滞痰凝、肝郁脾虚、气阴两虚,治疗以行气化痰... 详细信息

甲状腺癌术后部分患者可出现咽部异物感、神疲乏力、食少纳呆、失眠多梦、心慌盗汗等不适症状,影响患者的日常生活,降低生活质量。赵先明认为甲状腺癌术后多本虚标实、虚实夹杂,常见证型为气滞痰凝、肝郁脾虚、气阴两虚,治疗以行气化痰、疏肝健脾、益气养阴为法,并注重对脾胃的调养,在临床上取得较好的疗效。

关键词：甲状腺癌术后中医药治疗

Mathematic modeling on flexible cooling system in hot strip mill

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Journal of Central South University 2014年第1期21卷 43-49页

作者：彭良贵刘相华赵宪明吴迪 State Key Laboratory of Rolling and Automation (Northeastern University)

A novel cooling system combining ultra fast cooling rigs with laminar cooling devices was *** on the different cooling mechanisms,a serial of mathematic models were established to describe the relationship between water flow and spraying pressure and the relationship between water spraying heat flux and layout of nozzles installed on the top and bottom cooling *** parameters were validated by measured *** transfer models including air convection model,heat radiation model and water cooling capacity model were detailedly *** addition,effects on cooling capacity by water temperature and different valve patterns were also ***,the comparison results from UFC used or not have been provided with respect to temperature evolution and mechanical properties of Q235B steel grade with thickness of 7.8 *** online application of the sophisticated CTC process control system based on these models,run-out table cooling control system has been running stably and reliably to produce resource-saving,low-cost steels with smaller grain size.

关键词： mathematic model ultra fast cooling laminar flow cooling variable frequency control coiling temperature control

XBRL技术下的企业财务报告——研究综述及启示

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经济与管理研究 2012年第2期33卷 120-128页

作者：赵现明华东师范大学商学院

XBRL是一种基于XML语言,通过对信息的标准化过程来节约交易成本的新型信息技术。本文将从XBRL财务报告的界定和组成开始,讨论了XBRL数据的特点和XML技术规范、XBRL技术规范、XBRL分类标准以及XBRL实例文档之间的关系。然后分别从实例文... 详细信息

XBRL是一种基于XML语言,通过对信息的标准化过程来节约交易成本的新型信息技术。本文将从XBRL财务报告的界定和组成开始,讨论了XBRL数据的特点和XML技术规范、XBRL技术规范、XBRL分类标准以及XBRL实例文档之间的关系。然后分别从实例文档的认定、信息标准的发展和扩散以及XBRL对资本市场的影响三个方面对以往文献进行了较全面的梳理。

关键词： XBRL 认定信息标准扩散

冷却时间对U75V 60kg/m重轨热处理硬化层的影响

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中南大学学报（自然科学版） 2012年第11期43卷 4242-4247页

作者：康皓赵宪明吴迪东北大学轧制技术及连轧自动化国家重点实验室辽宁沈阳110819

将U75V 60 kg/m重轨试样加热至900℃,保温50 min后,用压缩空气对轨头表面进行强制冷却50~90 s,研究U75V 60 kg/m重轨热处理硬化层与冷却时间之间的关系。研究结果表明：热处理过程中,冷却时间大于80 s时,轨头中心表面自回火温度低于在... 详细信息

将U75V 60 kg/m重轨试样加热至900℃,保温50 min后,用压缩空气对轨头表面进行强制冷却50~90 s,研究U75V 60 kg/m重轨热处理硬化层与冷却时间之间的关系。研究结果表明：热处理过程中,冷却时间大于80 s时,轨头中心表面自回火温度低于在该冷却速率下珠光体转变终止温度,珠光体相变完成;重轨热处理后硬化层组织为细珠光体,随着冷却时间的增加,珠光体平均片层间距减小,但趋势放缓,当冷却时间为90 s,离轨头中心表面3 mm处珠光体平均片层间距约为83 nm;随着冷却时间的增加,硬化层厚度增大,硬度、抗拉强度、伸长率及冲击韧性提高,当冷却时间大于80 s时,性能趋于稳定。

关键词：冷却时间重轨热处理硬化层