机械活化-反应热处理制备纳米晶WC-Co复合粉末

以W,C,Co为原料粉末,经机械活化-反应热处理工艺制备纳米晶WC-Co复合粉末。结果表明:活化粉末的固相反应具有以下特征:反应温度低,反应速度快。在800℃热处理时已有大量WC生成。在850℃保温25minW2C完成了向WC的转化。经900℃保温35min制备了晶粒尺寸为30.5nm的WC-Co复合粉末。     

双尺度 WC-CoCr 涂层的组织结构分析

微纳米复合结构的碳化钨涂层的性能引人关注。以纳米碳化钨(≤200nm)、亚微米碳化钨(0.8μm)和微米碳化钨(2μm)为原料,制备了两种双尺度的微纳米复合结构碳化钨喷涂粉末,采用超音速火焰喷涂工艺制备了相应的涂层。利用扫描电镜、能量色散X射线光谱仪和透射电镜对涂层的物相结构进行了分析。结果表明,纳米微米复合粉涂层中的碳化钨保留率为96.7%;纳米亚微米复合粉末制备的涂层碳化钨保留率为92.5%。两种涂层中,W_2C均分布在WC附近,大颗粒WC颗粒仍保持原来的尖角形,小尺度WC颗粒部分呈圆角形,纳米-亚微米涂层中Co_3W_3C相分散于WC与非晶相之间。     

铸造碳化钨反应烧结制备粗晶硬质合金

以铸造碳化钨和钻为原料在低温条件下制备η相粉末,将该粉末与炭黑混合球磨、压制成形,在1450℃的真空条件下反应烧结制备粗晶硬质合金.探讨烧结气氛、烧结温度对合成η相的影响,碳含量对硬质合金物相、显微组织和物理性能的影响.结果表明在1 200℃的氮气气氛中合成了含有Co2W4C和Co6W6C的混合η相粉末;当总碳含量为5...     

世界首条水溶化学法钨冶炼生产线投产

福建金鑫钨业股份有限公司投资建设的水溶化学法制备纳米级碳化钨钴(WC-Co)复合粉技术项目,日前建成一条年产600t的工业化生产线并正式投产,从而在全球首次将全部原料通过水溶法工业化制备纳米碳化钨钴复合粉。该项目以水溶法生产的超细纳米WC-Co复合粉末为原料,制备具有双高(高耐磨性、高韧性)特性的超细晶硬质合金,产品抗温强度可以达到4000     

碳化钨-抑制剂复合粉末及其超细硬质合金的制备方法

该发明涉及一种碳化钨-抑制剂复合粉末及其超细硬质合金的制备方法。首先制备含碳和抑制剂的氧化物粉末,然后采用直接还原碳化法合成碳化钨-抑制剂复合粉末．添加金属粉末后进行球磨混合、干燥、成型、真空烧结或氢气烧结后热处理,或直接低压烧结,得到超细或纳米碳化钨基硬质合金。该发明解决了已有技术存在抑制剂后期添加不均匀或抑制剂在前期添加时只能采用碳化温度低的抑制剂的缺陷。可使多种抑制剂在前期引入并保证其在碳化钨基体中的均匀分散,所用原料都采用环保性化合物,制备温度低于传统制备方法,工艺简捷安全,生产成本低,易实现产业化。     

超细及纳米WC-Co复合粉的低成本短流程制备及应用

综述了在超细及纳米WC-Co粉末的制备研究方面国内外的相关研究进展,系统介绍了北京工业大学硬质合金研究组在研究开发超细及纳米WC-Co复合粉的原位反应合成技术、超细及纳米复合粉在金属陶瓷防护涂层及烧结硬质合金块体材料中的应用等方面开展的系列工作和取得的研究结果。以合成的WC-Co复合粉为原料,制备的超细结构硬质合金涂层、超细晶及纳米晶硬质合金块体材料均具有优良的综合性能。     

WC—Co复合粉末的流态化合成及其应用

简要介绍了采用钨钴液相复合－喷雾干燥－流态化热化学转化工艺（ＳＣＰ）合成超细碳化钨钴复合粉末的新方法,以该粉末制备的硬质合金工艺进行了初步探讨,结果表明：这种方法合成的碳化钨钴复合粉末具有分子水平的均匀组成及超细的平均晶粒度,制备的硬质合金硬度ＨＲＡ大于９２．０,抗弯强度大于３３００ＭＰａ。     

WC-Co复合粉末的流态化合成及其应用

简要介绍了采用钨钴液相复合—喷雾干燥—流态化热化学转化工艺(SCP) 合成超细碳化钨钴复合粉末的新方法,以该粉末制备的硬质合金工艺进行了初步探讨,结果表明:这种方法合成的碳化钨钴复合粉末具有分子水平的均匀组成及超细的平均晶粒度( 小于100nm),制备的硬质合金硬度HRA大于92.0,抗弯强度大于3300 MPa     

喷雾转化法纳米WC/6Co复合粉形貌研究

纳米碳化钨钴复合粉体具有重要的工程应用和市场发展潜力。针对纳米碳化钨钴复合粉形貌难以精确控制这一问题,本文以偏钨酸铵(AMT)、可溶性钴盐、有机碳源为原材料,以蒸馏水为溶剂,不添加WC晶粒长大抑制剂,制备钨钴碳混合溶液,再采用喷雾转化(SCP)和连续低温还原碳化法制备了纳米碳化钨钴复合粉;研究了喷雾转化过程中溶液浓度、进料速度、离心转速和转化温度4个关键因素对纳米碳化钨钴复合粉松装密度、WC晶粒度及微观形貌的影响。研究表明:通过喷雾转化法制备的纳米碳化钨钴复合粉呈空壳球形结构,Co相发生熔化使大多WC被粘结在一起,WC颗粒之间存在明显的烧结颈,颗粒表面存在大量孔隙,部分颗粒存在破裂现象;WC平均晶粒度小于200 nm;离心转速是影响粉末松装密度、WC晶粒度及颗粒形貌的最主要因素;离心转速越大,复合粉末颗粒越小,松装密度越大;同时转化温度越高,WC晶粒度越小,复合粉末颗粒越易破裂。     

专利信息

一种碳化钨一钴,二硫化钼复合粉末及其制备方法;一种从仲钨酸铵结晶母液中回收钨和氯化铵的方法;纳米碳管-纳米碳化钨复合粉体的制备方法     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.