共查询到20条相似文献,搜索用时 15 毫秒
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实现金属材料凝固组织均匀、细化是当今工业生产中的重要研究方向,本文综述了国内外运用电脉冲细化金属凝固组织的研究现状,以及影响细化效果的各种因素.对细化机理进行了概况总结,并对研究不足以及今后发展方向进行了阐述. 相似文献
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Wen-Bin Dai Xiu-Li Zhou Xin Yang Guang-Peng Tang Dan-Bin Jia Nai-Liang Cheng Jing-Kun Yu 《金属学报(英文版)》2016,29(5):500
In this work, low-density electric current pulse(ECP) has been applied to submerged entry nozzle(SEN) and its effect on the morphology of the inclusion buildup and the distribution of the inclusions in slab has been explored. The results reveal that under the unique effects of ECP, part of small inclusions less than 10 lm is expelled through the boundary layer along the current direction to form dense inclusion buildup. This method is of great potential to prolong the service life of SEN and improve the quality of the steel product. 相似文献
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高密度脉冲电流作用下LY12铝合金的凝固组织 总被引:22,自引:6,他引:22
研究了高密度脉冲电流作用下LY12铝合金的凝固组织,试验结果表明嵩密度的脉冲电流可明显地改善该合金凝固组织。和未经电流处理的样品相比,其组织明显细化和等轴化,且脉冲电流愈强,且脉冲电流愈强,这种效果愈显著。 相似文献
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Supov A. V. Prusakov B. A. Aleksandrova N. M. Kakabadze R. V. 《Metal Science and Heat Treatment》2002,44(1-2):47-48
Metal Science and Heat Treatment - 相似文献
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脉冲电流对金属凝固组织影响的研究进展 总被引:1,自引:0,他引:1
韩伟 《中国铸造装备与技术》2007,(5):2-6
综述了脉冲电流对金属凝固组织的影响及细化机制的研究现状及进展.分析了脉冲电流对不同合金凝固组织细化的影响,其细化效果与金属的固有性质,脉冲电流施加于合金凝固过程的不同阶段及作用时间的长短有密切关系,从理论和实践上归纳和分析脉冲电流对凝固组织细化的机制主要是:促进形核,晶核增殖和抑制晶体生长. 相似文献
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研究了脉冲电流对Al-4.5Cu合金定向凝固过程及组织的影响。结果表明,随着脉冲电流峰值和频率的增大,Al—4.5Cu合金柱状晶被熔断,形态由细条状变为不连续,失去其定向凝固的取向性;且柱状晶间距随电流峰值和频率的增大而减小。由脉冲电流的引入而产生的脉冲磁压力及焦耳热效应在固液界面处造成的强烈扰动是定向凝固组织失去取向性的主要原因。 相似文献
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在脉冲电场作用下45钢淬火新工艺 总被引:1,自引:1,他引:1
研究了45钢在脉冲电场作用下淬火的新工艺。结果表明:45钢在脉冲电场作用下淬火,在保证得到良好马氏体组织的同时,又可以降低淬火加热温度,其硬度可比普通淬火高3~5HRC。 相似文献
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直流电沉积和脉冲电沉积Ni-W涂层的对比研究(英文) 总被引:1,自引:0,他引:1
采用脉冲电沉积和直流电沉积方法在中碳钢基底上沉积了具有不同W含量的Ni-W涂层。应用能谱仪(EDS),扫描电子显微镜(SEM),X射线衍射仪(XRD)分别表征了涂层的成分、形貌和结构,分别研究了涂层的硬度和耐腐蚀性能。结果表明,脉冲电沉积涂层具有均匀表面,致密的结构,其硬度和耐腐蚀性能比直流电沉积涂层更高。钨含量高于20at%的脉冲电沉积涂层具有纳米晶结构,其中含钨量最高的脉冲电沉积涂层的HV硬度可高达7.26GPa。中性盐雾试验结果表明,脉冲电沉积Ni-W涂层耐蚀性优于直流电沉积涂层,是有效的可替代电镀Cr的材料。 相似文献
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Dina V. Dudina Igor S. Batraev Vladimir Yu. Ulianitsky Natalia V. Bulina Michail A. Korchagin Ivan A. Bataev Alberto Moreira Jorge Jr. 《Journal of Thermal Spray Technology》2014,23(7):1116-1123
In thermally sprayed coatings, nano-sized features of the microstructure may be either inherited from the nanostructured agglomerates of the feedstock powder or form as a result of rapid cooling of molten particles upon deposition. Applying a process of the computer-controlled detonation spraying (CCDS) to Ti3SiC2-Cu composite powders produced by high-energy mechanical milling, we show that both routes are possible depending on the spraying conditions. When the nanostructure of the Ti3SiC2-Cu coating is inherited from the feedstock powder—under very mild conditions of detonation spraying, which exclude melting, so is the phase composition of the coating. In higher-temperature conditions of spraying, a significant fraction of the copper matrix melts and the interaction between Ti3SiC2 and Cu occurs. The TiC x -Cu(Si) coatings that form show crystallites of both phases in the nano-range. In this case, rapid solidification of the molten fraction of the particles is responsible for the formation of the coatings with a nanostructured matrix. Due to the flexibility of the CCDS process, conditions of spraying were found such that a composite coating with very fine crystallites of the Cu(Si) matrix (30 nm) and a hardness of 273 HV could be obtained. 相似文献