Al对MoSi2材料干摩擦磨损性能的影响

运用M－2型摩擦磨损试验机测定了不同载荷条件下Al／MoSi2材料与45钢配对时的干摩擦磨损性能，采用SEM观察了摩擦副表面的形貌，利用X－ray分析了相组成，并探讨了其磨损机制。结果表明：少量Al的添加降低了MoSi2材料的摩擦磨损性能，其摩擦系数和磨损率均可用负荷的4项式表示。随负荷增大，Al／MoSi2材料的磨损机制主要表现为微切削、粘着磨损和凿削式磨粒磨损。     

干摩擦条件下MoSi2／45钢摩擦磨损性能的研究

通过着重研究MoSi2和45钢对摩时的干摩擦磨损性能，在扫描电子显微镜（SEM）下观察了磨损表面的形貌，分析了其摩擦磨损机理。结果表明：随SiO2氧化膜的产生与剥落，摩擦系数随摩擦行程的延长呈不规则变化，MoSi2材料表现出优良的耐磨性能，其稳定磨损率小于0．04g/km。随着磨损载荷的增，摩擦机理主要从微观滑移、塑性变形转变为粘着效应；磨损机理主要从磨粒磨损、氧化疲劳磨损转变为粘着磨损。     

载荷影响MoSi2材料磨损特性的研究

在M-200型摩擦磨损试验机上,评价了载荷对金属间化合物MoSi2/45钢在干摩擦状态下磨损特性的影响,利用扫描电子显微镜(SEM)观察了磨损表面形貌,并利用微探针和X射线衍射仪分别分析了磨损表面微区成分和磨屑成分。结果表明:载荷明显影响MoSi2材料的磨损特性,随着载荷的变化,磨屑成分有所不同,磨损机理主要从脆性断裂和微切削、氧化疲劳磨损转变为粘着磨损。     

二硅化钼在油润滑下的摩擦学性能研究

利用摩擦磨损试验机,在20~＃机油润条件下研究了金属间化合物MoSi2的摩擦磨损行为,探讨了MoSi2材料的磨损机制。结果表明;20~＃机油润滑可有效地降低MoSi2摩擦副的摩擦系数和材料的磨损率,由于对磨偶件硬度的不同,MoSi2材料的磨损机制稍有差异,MoSi2/CrWMn钢配副性能较好。     

载荷对原位无压烧结MoSi2基复合材料磨损性能的影响

通过原位烧结的方法成功制备出SiC-WSi2-MoSi2复合材料,并在XP-5型高温摩擦磨损试验机上考察了SiC-WSi2-MoSi2复合材料与Al2O3陶瓷对磨时的摩擦磨损特性.采用带微探针的扫描电子显微镜(SEM)观察与分析了SiC-WSi2-MoSi2复合材料的磨损表面形貌及成分组成,并讨论了其磨损机理.实验结果表明:复合材料的磨损过程可分为3个阶段:跑合阶段、过渡期和稳定磨损;MoSi2基复合材料的磨损机理随着载荷变化而变化,依次表现为氧化、粘着、研磨和疲劳磨损.Al2O3的磨损机制为粘着和疲劳磨损.     

载荷对MoSi2高温磨损性能的影响

采用高温自蔓延合成了MoSi2粉末,经冷压和高温真空烧结成试样。在XP-5型高温摩擦磨损试验机上,考察了MoSi2与Al2O3陶瓷在1 000℃对摩时的摩擦磨损特性。通过带微探针的扫描电子显微镜（SEM）观察与分析了试样表面的磨损形貌及成分组成,并讨论了其磨损机理。结果表明,MoSi2的高温磨损过程存在跑合、过渡期和稳定磨损3个阶段,小于50 N时该材料具有较好的耐磨性;虽然粘着磨损普遍存在,但随着载荷的增大,MoSi2的磨损机理依次还表现出研磨、塑性变形与疲劳断裂。     

油润滑下MoSi2/CrWMn钢摩擦磨损性能的研究

在M—200型摩擦磨损试验机考察了MoSi2／CrWMn钢在20^#机油润滑条件下的摩擦学性能，并比较了该摩擦副在干摩擦条件下的摩擦磨损特性。运用扫描电子显微镜和定点探针观察与分析了摩擦副的表面形貌及其微区成分，讨论了其磨损机理，并探讨了MoSi2材料的配副特性。试验结果表明：润滑油改善了MoSi2材料的摩擦学性能，MoSi2／CrWMn钢的主要摩擦机理为塑性变形，MoSi2材料的磨损机制主要表现为疲劳磨损和磨粒磨损。高硬度CrWMn钢适合作MoSi2的配副材料。     

MoSi2/CrWMn钢干摩擦磨损特性及磨损机理的研究

研究了干摩擦条件下MoSi2与CrWWn钢对摩时的摩擦磨损特性，通过扫描电子显微镜（SEM）和X射线衍射仪观察与分析了试样表面的磨损形貌以及磨损的物相组成，并讨论了其磨损机理，结果表明，MoSi2材料的磨损机理依载荷变化而变化，低载荷（30～50N）作用下，其主要磨损机理为疲劳磨损，较高载荷（80～150N）作用时，又转化成为粘着磨损为主。     

激光熔覆镍基纳米Al2O3复合涂层的组织和摩擦性能

采用激光熔覆技术在45钢基体上制备了镍基纳米Al2O3复合涂层,对熔覆层进行了微观组织分析和显微硬度及摩擦性能测试.结果表明,激光熔覆层的组成相主要为γ(Fe,Ni)、Cr7(B,C)3、Al15Fe4等,熔覆层的显微硬度HV0.3最高达到830,熔覆层与纯铝试件对摩时的磨损机制为粘着,并且随pv值增大时,粘着现象加剧,摩擦因素增大.     

TiC/Cu复合材料的摩擦性能分析

为提高TiC/Cu复合材料的摩擦性能,对不同TiC掺量条件下TiC/Cu复合材料的摩擦磨损性能进行试验分析,研究结果表明：与基体试样相比复合材料的磨损系数较低,且在低载荷磨损时磨损性能更佳,TiC含量增加到3%时的摩擦系数最低。通过磨损形貌分析发现,基体材料主要为黏着磨损,复合材料的磨损行为表现为氧化、粘着和剥层磨损,且复合材料中的TiC颗粒能很好的抵抗粘着磨损的作用,从而使得复合材料的磨损表面磨损程度减轻。     

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