| 引用本文: | 牛立斌,许云华,武宏,崔雅茹.电磁场作用下原位生成WC颗粒机理的研究[J].材料科学与工艺,2010,18(4):550-554.DOI:10.11951/j.issn.1005-0299.20100423. |
| NIU Li-bin,XU Yun-hua,WU Hong,CUI Ya-ru.Study on the mechanism of in-situ synthesized WC particles by exerting electromagnetic field[J].Materials Science and Technology,2010,18(4):550-554.DOI:10.11951/j.issn.1005-0299.20100423. |
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| 摘要: |
| 为了提高灰口铸铁的耐磨性,用施加电磁场的方法,在灰口铸铁熔体中原位合成了WC颗粒,采用X射线衍射仪、扫描电子显微镜、能谱分析仪研究了合成产物的物相、显微组织以及化学成分.实验结果表明:提高电磁频率有助于WC颗粒的原位合成,当电磁频率5kHz、电流为15A、作用时间为5min时,可得到细小,且分散性较好的颗粒.主要是电磁场的存在,降低了钨丝的表面张力,使钨原子容易从表面脱附,同时提高了钨丝附近的Fe-W-C三元体系微小区域的混合熵,引起了生成WC颗粒的自由能降低,从而利于WC颗粒的合成. |
| 关键词: 原位反应 钨丝 WC 反应机理 |
| DOI：10.11951/j.issn.1005-0299.20100423 |
| 分类号:TB331 |
| 基金项目:陕西省2007年“13115”科技创新工程技术研究中心项目(2007ZDGC-17) |
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| Study on the mechanism of in-situ synthesized WC particles by exerting electromagnetic field |
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NIU Li-bin1,2, XU Yun-hua1, WU Hong1, CUI Ya-ru1
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1.Institute of Wear Resistance Material,School of Mechanical and Electrical Engineering,Xi’an University of Architecture & Technology,Xi’an 710055,China;2.College of Material Science and Engineering,Xi’an University of Technology,Xi’an 710055,China
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| Abstract: |
| In order to improve the wear resistance of gray cast iron,tungsten carbide particles(WC) were in-situ synthesized in the gray cast iron matrix by applying electromagnetic field technique.The phases,microstructure and chemical composition of the products were investigated by scanning electron microscope(SEM),energy dispersive X-ray spectrometry(EDS) and X-ray diffractometer(XRD).The results show that,with increasing the electromagnetic frequency,the amounts of the tungsten carbide particles will be enhanced.When the experimental frequency,current and time parameters are 5 KHz,15 A and 5 min,respectively,the fine and good dispersive particles can be obtained.Due to the effect of the electromagnetic field,the surface tension of tungsten wire decreases;tungsten atoms can be easily detached from the surface and rapidly diffused into the molten.Then,the reaction entropy increases in the small zones of Fe-W-C ternary system,which are formed surrounding the tungsten wires,this leads to the decrease of free energy of WC and is beneficial to synthesize WC particles. |
| Key words: in-situ synthesis tungsten wire WC reaction mechanism |
