检索结果-南通市图书馆

Effects of correlative factors on the interdendritic melt flow brought by the bulge in continuous casting slabs

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Journal of University of Science and Technology Beijing 2008年第4期15卷 407-411页

作者： Shuying Chen Guowei Chang Jianzhong Wang chunjing wu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Materials and Chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China

The effects of various factors on the flow speed of interdendritic melt were analyzed in detail in the process of continuous casting slabs. When the solid-liquid interface bends periodically, the expression of solute distribution in the columnar crystal zone was deduced, and the quantitative calculation was also made. The results show that the bulge and the interdendritic spacing are responsible for the flow speed of interdendritic melt. At the initial stage of solidification the bulge operates, and at the final stage the interdendritic spacing operates. The experimental results of macrosegregation in the slabs validated the calculated results of the flow speed of interdendritic melt, which shows that the calculated results are basically consistent with the experimental ones.

关键词： continuous casting two-phase region melt flow macrosegregation

Orthogonal tests of copper-clad aluminum bimetal continuous casting by nitrogen pressure core-illing

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China Foundry 2013年第6期10卷 385-390页

作者： Xue Zhiyong Liang He Yu Wanhua wu chunjing School of Energy and Power Engineering North China Electric Power University Beijing General Research Institute for Nonferrous Metals School of Materials Science and Engineering University of Science and Technology Beijing

To provide theoretical basis and practical guidance for preparing composite rods by direct continuous casting, copper-clad aluminum composite rods of external copper layer diameter 12 mm and inner aluminum core diameter 8 mm were manufactured. Orthogonal tests consisted of three factors and three levels were carried out to research the effects of melting copper temperature, continuous casting speed and nitrogen pressure on the performance of composite rods. Results showed that nitrogen pressure is the most important factor in influencing the surface quality; continuous casting speed is the most important factor in influencing copper & aluminum inter diffusion amount. Nitrogen pressure can noticeably improve the surface quality and make the rods easily be drawn out, but the surface quality does not show visible improvement when the nitrogen pressure is above 0.05 MPa. Measured by tests, the compound layer can be divided into three types according to its cladding layer degree: deficient cladding, normal cladding and excess cladding. The diameter of normal copper-clad aluminum composite rods can be successfully drawn less than 0.6 mm without annealing.

关键词： copper-clad aluminum nitrogen pressing continuous casting orthogonal test

Continuous unidirectional solidification of QAl9-4 Cu-Al alloy

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中国有色金属学会会刊：英文版 1999年第3期9卷 493-499页

作者： Chang Guowei(常国威) Yuan Junping(袁军平) Wang Zidong(王自东) wu chunjing(吴春京) Hu Hanqi(胡汉起) Miao Zhimin(苗治民) Beijing Univ Sci & Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

A continuous unidirectional solidification equipment with the advantages of electric slag remelting, induction heating, continuous casting and unidirectional solidification was built to study the QAl9 4 Cu Al alloy. The results show that the electro slag induction continuous unidirectional solidification process can be used for the steady continuous unidirectional solidification of QAl9 4, and revitalizes the down pulling continuous unidirectional solidification process; that the temperature distribution in the mold wall reflects that of the molten metal in the mold, thus the temperature distribution in the mold wall can be used to control the electric slag induction continuous unidirectional solidification process; and that the mutual matching of the technological parameters is the key to stabilize the solidification process.

关键词： QAl9 4 Cu Al alloy continuous casting electro slag remelting unidirectional solidification

Preparation of Single Crystal Copper with Large Diameter and Evolution of Solidification Structure

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稀有金属材料与工程 2011年第S3期40卷 198-201页

作者： Yuan Baolong, Zhang Hong, Wang Zidong, wu chunjing University of Science and Technology Beijing, Beijing 100083, China Univ Sci & Technol Beijing Beijing 100083 Peoples R China

Single crystal copper with large diameter is prepared in vacuum induction furnace under the protection of argon using downward continuous unidirectional solidification method. The process parameters are determined through the experiments. The effects of the process parameters on solidification structure and surface quality of the single crystal copper with large diameter are investigated. The results show that single crystal copper of Φ16 mm with bright surface can be obtained continuously and stably under the following conditions: melting temperature is 1150 ℃, outlet temperature of mold is 750 ℃, cooling water volume is 0.9 m3·h-1, cooling distance is 50 mm, and drawing speed is 0.1 to 0.15 mm·s-1. By X-ray diffraction, the orientation and competition growth of single crystal copper have been analyzed, and the crystallization surfaces of (311), (220) and (111) are eliminated sequentially during evolutionarily processing. The final growth face of single crystal copper is (200). its direction of crystallization is [100]. Effect of solid-liquid interface on crystal growth has been investigated, the micro-convex interface to liquid is the key to getting single crystal copper.

关键词： unidirectional solidification single crystal copper solidification structure crystal orientation solid-liquid interface

Effect of ferrovanadium inoculation on microstructure and properties of high speed steel

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China Foundry 2008年第2期5卷 95-98页

作者： Zhang Xipeng Kou Guojun wu chunjing Gan Zhaiping Zhao Wanzi Chuan Xiangzhao Ma Ye School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China wuhan Iron and Steel Group Co. Wuhan 430083 China

The effect of ferrovanadium inoculation on the microstructure and properties of high speed steel (HSS) used for rolls was studied. The results showed that the as-cast eutectic carbide network tends to be broken after ferrovanadium inoculation, and the carbides are changed to rod-like or nodular shape. After heat treatment, the carbides in the inoculated HSS are spheroidized and distributed more uniformly in the matrix. The impact toughness of high speed steel with ferrovanadium inoculation is obviously improved. The action mechanism of ferrovanadium inoculation on the microstructure of the alloy is also discussed.

关键词： high speed steel carbides inoculation

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连铸铜包铝复合棒坯过渡层的研究

特种铸造及有色合金 2005年第5期25卷 304-306页

作者：秦延庆薛志勇吴春京北京科技大学

在双金属连铸铜包铝复合棒坯试验中,出现不同过渡层的制品。对试验中出现的不同制品进行分析研究,结合试验条件分析其中的极端现象———芯部全为化合物的试样的成分及其产生的原因,在此基础上进一步探讨如何控制过渡层的厚度,改进产品... 详细信息

在双金属连铸铜包铝复合棒坯试验中,出现不同过渡层的制品。对试验中出现的不同制品进行分析研究,结合试验条件分析其中的极端现象———芯部全为化合物的试样的成分及其产生的原因,在此基础上进一步探讨如何控制过渡层的厚度,改进产品质量。

关键词：双金属连铸铜包铝复合捧坯过渡层化合物温度拉速

充芯连铸铜包铝棒坯工艺参数对表面质量的影响

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特种铸造及有色合金 2006年第2期26卷 121-123页

作者：薛志勇吴春京谢建新北京科技大学

在自制的连铸设备上，通过工艺参数的合理匹配，成功地制备出外层为铜内层为铝，外径为40mm、铜壁厚为8mm、长为80cm的铜包铝棒坯。试验发现铜液的熔化温度、结晶器水冷铜套与石墨衬套的接触长度、连铸速度、二次冷却水的位置和流量对... 详细信息

在自制的连铸设备上，通过工艺参数的合理匹配，成功地制备出外层为铜内层为铝，外径为40mm、铜壁厚为8mm、长为80cm的铜包铝棒坯。试验发现铜液的熔化温度、结晶器水冷铜套与石墨衬套的接触长度、连铸速度、二次冷却水的位置和流量对固液界面、铜管的表面质量以及复合界面铜铝的相互扩散都有很大的影响。合理匹配可使固液界面位置调整到离结晶器出口端5～10mm处，复合棒坯表面光洁、复合良好，经过挤压与拉拔，可以制成不同直径的铜包铝复合线。

关键词：连续铸造铜包铝复合棒坯工艺参数固液界面铜包铝线

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充芯连铸铜包铝复合材料制备技术的试验研究

特种铸造及有色合金 2008年第5期28卷 383-384页

作者：薛志勇吴春京张智华北电力大学能源与动力学院电站设备状态监测与控制教育部重点实验室北京102206 北京科技大学材料科学与工程学院山西省机电设计院

在自行研制的充芯连铸工艺试验机上,通过工艺参数的合理匹配,成功地制备出质量较好的外层为铜、内层为铝的铜包铝棒坯。对复合坯经过静液挤压与拉拔,制成不同直径的铜包铝复合线。对铜包铝线的显微硬度和导电性能、力学性能的检测表明,... 详细信息

在自行研制的充芯连铸工艺试验机上,通过工艺参数的合理匹配,成功地制备出质量较好的外层为铜、内层为铝的铜包铝棒坯。对复合坯经过静液挤压与拉拔,制成不同直径的铜包铝复合线。对铜包铝线的显微硬度和导电性能、力学性能的检测表明,其外观、导电性能和力学性能达到了国家标准。

关键词：铜包铝线充芯连铸复合材料

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430铁素体不锈钢钢卷工艺和性能分析

哈尔滨工业大学学报 2015年第3期47卷 107-110页

作者：刘洪涛吴春京任学平李殊霞北京科技大学材料科学与工程学院北京100083 太原钢铁(集团)有限公司技术中心太原030003

为改善430铁素体不锈钢的性能,主要研究了化学成分、铸坯等轴晶比例、热轧工艺制度、热卷退火工艺对材料组织和性能的影响.通过添加微量铝元素,同时降低过热度浇注,优化电磁搅拌工艺改善铸坯的结构.实验结果表明,通过不同热处理对比试... 详细信息

为改善430铁素体不锈钢的性能,主要研究了化学成分、铸坯等轴晶比例、热轧工艺制度、热卷退火工艺对材料组织和性能的影响.通过添加微量铝元素,同时降低过热度浇注,优化电磁搅拌工艺改善铸坯的结构.实验结果表明,通过不同热处理对比试验确定了最佳热处理工艺,热卷退火温度为950-1 000℃,保证了成品材料具有优异的力学性能和工艺性能.

关键词：化学成分热处理制度组织性能