涡轮式压缩机引线铜管失效原因分析

针对技术成熟度较高的涡轮式压缩机泄漏失效问题,采用金相显微镜、扫描电镜、能谱仪、维氏显微硬度仪等技术手段,对泄漏部位进行分析．结果表明：泄漏部位为压缩机引线铜管,铜管泄漏失效机制为疲劳失效;泄漏失效原因为压缩机引线铜管材质硬度过高,不适宜再次机械加工,并且机械加工工艺与铜管硬度不相适应．      

钙钛矿型LaSrFeO4的光学特性研究

采用固相反应法制备了LaSrFeO⁴钙钛矿材料,并且在较大的频率范围内测量了其反射率,然后利用Kramers-Kronig关系(K-K关系)计算了LaSrFeO⁴的光学参数,即折射率和介电常数．在得到光学参数的基础上,计算了LaSrFeO⁴的电导率,计算结果与其他课题组公开报道的结果符合的很好．      

原子层沉积薄膜的表征方法进展

原子层沉积（ALD）是一种新兴的薄膜沉积技术,其最主要的优势在于可在高深宽比的结构上沉积均匀致密的纳米薄膜,因此在微电子、纳米科技等领域中具有广泛的应用．纳米厚度的ALD薄膜与传统微米厚度的薄膜材料相比,需要更精确的表征手段,因此对ALD薄膜的表征方法展开了针对性探讨．阐述了ALD薄膜的常用物性表征方法,主要从薄膜厚度、成分、结晶性及形貌等方面展开探讨,同时展望了其未来发展的方向．      

废弃PET降解产物改性PC复合材料的制备及其性能

为提高聚碳酸酯（PC）材料流动性,以乙二醇（EG）为溶剂降解废弃聚对苯二甲酸乙二醇酯（PET）得到的产物为改性剂,制备PET降解产物改性的PC复合材料,对测试结果进行分析讨论。结果表明,PET降解反应中产物主要BHET及其低聚物,降解产物的加入能够有效提高复合材料熔体质量流动速率,且熔体质量流动速率随着降解产物添加量的增加而增大．综合分析复合材料的力学性能及流动性,确定最佳实验用量为4%,降解体系为m(PET)∶m(EG)为1∶3．      

包装用丙烯酸酯压敏胶的制备与研究

以软丙烯酸丁酯（BA）、丙烯酸异辛酯（2-EHA）、甲基丙烯酸甲酯（MMA）、丙烯酸(AA)、丙烯酸羟乙酯（HEA）为原料,采用预乳化半连续乳液聚合法制备丙烯酸酯压敏胶,研究了软/硬单体配比和功能单体含量对压敏胶初粘性、持粘性和180 °剥离强度粘结性能的影响．实验结果表明,在软单体、硬单体、功能单体的配比为47.5∶10∶5和T^g=-30.4 ℃条件下,采用滚球斜坡停止法测定初粘力,滚球选择20号钢球,丙烯酸酯压敏胶的持粘力达到34 min,180 °剥离强度为0.26 N/mm．表明,乳液稳定好、黏度适中,涂布效果理想．      

二氧化碳基TPU/淀粉共混材料性能的研究

以二氧化碳基TPU和玉米淀粉为原料,通过运用转矩流变仪制备一种综合性能优异的二氧化碳基共混材料．运用扫描电子隧道、电子拉力机、转矩流变仪和高压毛细管流变仪,分别研究了不同淀粉含量、不同温度对二氧化碳基共混材料的力学性能和流变性能的影响．结果表明：淀粉含量的增加会使得共混材料的拉伸性能和撕裂性能出现先增大后减小,当淀粉含量为30%时综合力学性能最好;温度的上升,会使得共混物的表观剪切应力和表观切黏度降低;随着淀粉含量的增加,共混物的综合加工性能逐渐下降．      

不同Mn含量及焊接电流对ER5356铝合金焊丝焊接性能的影响

为研究不同Mn含量ER5356铝合金焊丝和焊接电流对焊接焊头性能的影响,实验使用含锰量为0.05%和0.15%的ER5356铝合金焊丝,分别在110,115和125 A焊接电流下,采用TIG焊接6082铝合金．结果表明：用ER5356(0.15%的Mn)铝合金焊丝焊接得到的焊接接头的性能整体优于ER5356(0.05%的Mn)焊丝焊接得到的焊接接头,因Mn元素可以改善焊接接头的力学性能,进而提高铝合金焊接质量;随着焊接电流的增大,焊缝成形质量提高,当焊接电流为125 A时,无焊接热裂纹等宏观缺陷,焊接接头断口几乎观察不到未焊透的现象, 焊接接头匹配系数最高达到0.71.      

金属性MoO2纳米材料的制备及电阻的微区测量

为了研究MoO²的本征电阻率,采用化学气相沉积法（CVD）在蓝宝石衬底上制备金属性MoO²纳米材料,随后将材料转移到SiO²衬底制备成双端电阻器件,在进行电压?电流曲线测量的同时,采用开尔文探针力显微镜（KPFM）研究不同偏压下MoO²纳米材料表面电势的空间分布．结果表明：传统测量时忽略了接触电阻和热效应的影响,导致测量结果偏高;测量的MoO²的本征电阻率为6×10_-5 Ω·cm,可以媲美高质量ITO薄膜电极．所以,MoO²作为一种廉价电极材料在电子器件中具有潜在的应用前景．      

氧化物钎料连接Al2O3陶瓷的研究现状

对氧化物钎料连接Al₂O₃陶瓷的研究现状进行了阐述,介绍了目前氧化物钎料连接Al₂O₃陶瓷的一般流程和工艺方法．主要介绍了用于Al₂O₃陶瓷连接的高温氧化物钎料和低温氧化物钎料,并且分别对钎料的成分、接头组织、连接温度、接头剪切强度及组织变化趋势等进行了总结,最后指出了氧化物钎料的优势和存在的不足,旨在为氧化物钎料连接Al₂O₃陶瓷的研究重点和发展方向提供参考．      

激光熔覆硬质颗粒增强高熵合金复合涂层研究进展

高熵合金因其独特的合金设计理念及优异的综合性能,逐渐成为表面工程领域的热门涂层材料之一,而激光熔覆技术已成为高熵合金涂层制备的主要手段之一．目前,激光熔覆制备的面心立方（FCC）或体心立方（BCC）单相的高熵合金涂层,由于强度-塑性不匹配而导致涂层综合性能不佳,限制了其工程应用．由于硬质颗粒增强FCC结构高熵合金涂层是解决强度?塑性匹配的重要途径,成为国内外学者研究热点之一．重点介绍了直接添加和原位合成硬质颗粒增强高熵合金熔覆涂层的研究现状,分析了硬质颗粒增强高熵合金复合涂层性能的主要影响因素,并对未来硬质颗粒增强高熵合金涂层研究方向进行了展望．      

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

2014 second batch of rare earth quota released

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矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586