氩弧熔覆TiB/FeB增强Fe基复合涂层组织与性能研究

以Fe粉、Ti粉和B粉为原料,利用氩弧熔覆技术在Q235钢基材表面制备出TiB/FeB增强Fe基复合涂层,应用SEM和XRD方法分析了涂层的显微组织.并测试了涂层的硬度和耐磨性.结果分析表明:在Q235钢表面成功制备了以α-Fe为基体,以TiB/FeB颗粒为增强相的复合涂层.性能分析结果表明:涂层的显微硬度可达1 100HV,涂层耐磨性较基体提高近12倍.复合涂层的磨损机理为显微擦伤式磨损.     

Q235钢表面氩弧熔覆B4C-Ti复合涂层组织与性能的研究

以B4C粉、Ti粉和Fe粉末为原料,采用氩弧熔覆技术在Q235钢基体表面制备出增强复合涂层。利用扫描电镜,X射线衍射仪,显微硬度仪和摩擦磨损试验机等对复合涂层的组织,相组成,硬度和耐磨性能进行了研究。结果表明:熔覆层相由α-Fe、颗粒状Ti C和Ti B构成,Ti C颗粒弥散分布在基体上,涂层显微硬度高达700HV0.2,耐磨性能比Q235钢基体提高约6倍。     

超音速活性电弧制备锅炉用耐磨涂层性能研究

以FeCrNiBSi丝材为喷涂材料,采用Flame Arc超音速活性电弧喷涂系统在Q235钢为基体的工业锅炉用材料表面制备出结合强度高、耐磨性强的涂层;通过金相观察、拉伸试验、摩擦磨损试验,分别评价FeCrNiBSi涂层的孔隙率、显微硬度、结合强度和耐磨损性能;并通过扫描电子显微镜观察涂层微观形貌和磨损形貌。结果表明,涂层与基体结合良好,界面处未见任何分离,涂层结构比较致密,孔隙较少,孔隙率为0.71%,硬度为720 HV0.3,与基体结合强度达到60 MPa。相对于Q235钢,FeCrNiBSi涂层具有优异的抗磨损性能,其抗磨损性能是Q235钢的28倍。FeCrNiBSi涂层磨损机理为显微犁削和黏着磨损,耐磨性良好,具有良好的应用前景。     

熔覆电流对等离子熔覆ZrB_2-ZrC铁基复合涂层组织与性能的影响

采用等离子熔覆技术,在Q235钢表面原位反应合成了ZrB_2-ZrC增强的铁基复合涂层,分析了等离子电流对涂层组织及性能的影响。在100A熔覆电流下制备的涂层,显微硬度可达1017.7HV_(0.2),在100N的载荷下涂层的摩擦系数和磨损体积明显低于Q235钢基体,涂层耐磨性显著提高。     

氩弧熔敷原位自生TiC／Ni60A复合涂层的滑动磨损特性

利用氩弧熔敷技术,以Ni60A自熔合金粉、钛粉和石墨粉为原料,在16Mn钢表面原位合成了TiC增强Ni基复合材料涂层以提高基体的耐磨性.借助扫描电镜、X射线衍射仪、显微硬度计对复合涂层的组织和性能进行了分析.结果表明:熔敷层与基体呈冶金结合,无裂纹、气孔等缺陷,TiC颗粒弥散分布于熔敷层中;复合涂层有很高的硬度,在室温干滑动磨损试验条件下具有优异的耐磨性能并随着(Ti C)含量的增加而提高.     

氩弧熔覆原位自生(Ti,Nb)C增强镍基复合涂层的抗磨性能

以Ti、C、Nb粉和Ni60A合金粉末为原料,采用氩弧熔覆技术在16Mn钢基材表面分别制备(Ti,Nb)C颗粒增强Ni60A复合涂层(C-Ti-Nb-Ni60A涂层)和Ni60A涂层。应用金相显微镜(OM)、扫描电镜(SEM)、X射线衍射(XRD)对2种涂层的显微组织和物相进行观察与分析,测试涂层的显微硬度和不同载荷下的磨损性能,分析磨损机制。结果表明:C-Ti-Nb-Ni60A复合涂层与基体间呈冶金结合,界面间无气孔和裂纹;C-Ti-Nb-Ni60A复合涂层的显微硬度较基体16Mn钢提高近5倍,较Ni60A涂层提高0.45倍;常温干滑动200 N载荷条件下,CTi-Nb-Ni60A复合涂层的耐磨性能较基体16Mn钢提高6倍,较Ni60A涂层提高近2倍。16Mn钢表面发生严重的磨粒磨损和粘着磨损,Ni60A涂层表面以磨粒磨损为主,C-Ti-Nb-Ni60A复合涂层的磨损机理为显微檫伤磨损。     

FeCrBSiC电弧喷涂层磨损及热腐蚀性能研究

设计开发了一种FeCrBSiC粉芯丝材,采用电弧喷涂技术在Q235钢基体上制备相应涂层,通过XRD、SEM、磨粒磨损试验机及高温箱式电阻炉等对其微观组织结构、磨粒磨损及热腐蚀行为进行表征,同时与工程中广泛应用的NiCrTi涂层进行了对比研究.结果表明,涂层均具有热喷涂典型的层状结构,且较为致密,孔隙率低于3％; Fe基涂层组织更为均匀,其氧化物含量显著低于Ni基涂层.所设计Fe基涂层平均显微硬度约为1107.3HV0.1,其耐磨性也更为优异,达到Ni基涂层4倍以上.两种涂层在650℃时的热腐蚀动力学曲线均呈抛物线形式,表面生成连续致密的氧化膜阻止了腐蚀介质向涂层内部的渗透,能够对基体起到有效的防护作用.     

焊接电流对铁基硼化物涂层的组织性能影响

采用氩弧熔敷技术,Fe Ti70粉末和B粉作为预制合金粉,在Q235钢表面原位合成铁基硼化物涂层,研究焊接电流对复合涂层组织和性能的影响.对涂层进行一系列组织性能表征,利用X射线衍射仪分析涂层物相组成,利用光学显微镜观察组织形貌及分布,同时使用显微硬度计测量涂层硬度.结果表明,涂层中主要有Ti B2、Fe2B、Fe B、Ti B增强相;当焊接电流从120 A增加到150 A时,硼化物晶粒变得粗大;显微硬度从基体到涂层的顶端呈现梯度上升,并且涂层平均显微硬度为1165HV0.1,约为基体的5倍.     

感应钎焊微纳米WC-Ni基复合涂层性能研究

以微米、纳米WC为增强相，自熔合金Ni60A为钎焊材料，采用感应钎焊的方法在Q235低碳钢基体上制备了微纳米WC—Ni基复合涂层。通过用扫描电镜观察涂层的显微组织、用X射线衍射分析相组成和用能谱分析涂层的成分，研究了纳米颗粒WC的加入对涂层的显微组织和相组成的影响，以及对涂层硬度和耐磨性能的影响。结果表明，在相同试验条件下，添加纳米WC的涂层中，相组成中WC相较多，并且出现了少量的W2C硬质相，提高了涂层的硬度和耐磨性。     

H13钢表面激光熔覆原位生成WC增强Ni60梯度涂层的组织及性能

在H13钢表面采用激光熔覆技术制备了WC增强Ni60梯度涂层,使用金相显微镜、扫描电镜、X射线衍射仪、显微硬度计、万能摩擦磨损实验机对涂层的显微组织、物相组成、显微硬度和摩擦磨损性能进行分析。结果表明,WC增强Ni60梯度涂层气孔、裂纹缺陷较少,能够与基体形成良好的冶金结合。梯度涂层表面物相主要有铁碳化合物(Fe_xC)和铁镍固溶体((Fe, Ni)₂₃C₆、Ni₄B₃)以及WC、W₂C、Cr₇C₃等陶瓷增强相。制备的梯度涂层使模具钢表面的硬度和耐磨性得到了显著提高,其表面显微硬度最高值约为基体的4倍,磨损量仅为基体的18%左右,磨损机理主要为粘着磨损、脆性剥落和磨粒磨损,能够延长模具的使用寿命,减少资源的浪费。     

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.