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and volume fraction of 5%, 10% and 15% on the microstructure and tribological properties of Al-based composite was investigated. Composites were produced by applying compocasting process. Tribological... with different rolling reductions on the dry sliding wear characteristics of Al matrix composites was also assessed. Hardness measurement and scanning electron microscopy were used for microstructural......
micro- powder before and after surface modification 颗粒表面改性前后增强Al复合材料的制备采用挤压铸造专利技术[10]. 挤压铸造工艺为: 预制块预热温度580~600℃, 浇铸温度850~950℃, 压铸压力70~80MPa, 保压时间180s. 材料制备过程中渗透压的变化由压力曲线测得. 铝合金-α-Al2O3接触角测定在STMD300型表...渗透压的影响 在Al2O3p/Al复合材料制备过程中, 影响Al熔体在Al2O3颗粒间渗透的因素很多, 如铝合金和模具的预热温度; 颗粒表面结构及体积分数; 铝合金的种类及制备方法等. 其中颗粒与Al熔体之间的润湿性是最重要的影响因素, 它决定着复合材料制备能否成功以及材料最终致密性的优劣. 界面润湿性越好, Al熔体在颗粒间就越容易渗透, 渗透压就越低; 或者说渗透压越小, 则表明界面润湿性也......
pure reagents CaCO3, Al2O3, SiO2 and Na2CO3. The effects of Na2O-doping on the formation mechanism of calcium aluminate compounds and the crystal property of 12CaO·7Al2O3 (C12A7) cell were studied... that the covalency of O-Na bond in Na2O-doped 12CaO·7Al2O3 cell is weaker than those of O-Ca and O-Al bonds. The free energy of the unit cell increases because of Na2O doping, which results......
Al和Mg共掺杂LiFePO4/C正极材料的电化学性能研究肖资龙1,张志杰1,王红强1,李庆余11. 广西师范大学化学与药学学院广西低碳能源材料重点实验室摘 要:采用高温固相法合成了LiFePO4/C和Al,Mg共掺杂的LiFe0.95Al0.03Mg0.02PO4/C复合材料.通过X射线衍射(XRD),扫描电子显微镜(SEM),能量仪(EDS),恒流充放电测试,循环伏安法(CV)等手段对材料的结构,形貌及电化学性能进行了表征.XRD结果表明,Al,Mg共掺杂后的样品并没有破坏LiFePO4的橄榄石结构,同时还增强了LiFePO4结构的稳定性,提高了电子导电性和Li+扩散速度;通过SEM和EDS观测到LiFePO4呈球形颗粒,并在复合样品中检测到有Al和Mg元素存在.分别以0.5C,1C,3C和5C倍......
紫铜表面高能离子注渗Ni,Al的研究 赵钢1,张艺2,刘俊友2,赵天林1 (1.北京永固运通表面合金科技有限公司,北京,101301;2.北京科技大学,北京,100083) 摘要:对紫铜表面进行高能离子注渗Ni,Al试验的对渗层组织,成分分布进行了观察与分析,并同单元注渗Ni实验进行了比较分析.结果表明,紫铜表面高能离子注渗镍的渗层与铜基体结合良好,由表及里镍含量呈梯度分布,紫铜高能离子注渗Ni,Al的渗层组织和渗Ni组织大致相似,渗层表面出现"贫Al现象",即铝向基体扩散,最终主要集中在渗层的中部. 关键词:紫铜; 高能离子; 渗镍; 渗铝; [全文内容正在添加中] ......
Al掺杂ZnO薄膜的制备及红外光学性能的研究 何大伟1,封宾1,王永生1,鞠长滨1,富鸣1,杜玙璠1 (1.北京交通大学,发光与信息技术教育部重点实验室,北京,100044) 摘要:采用溶胶-凝胶法合成Al掺杂ZnO胶体,通过浸涂法在石英衬底上制备不同退火温度的ZAO薄膜.通过XRD,FT-IR,IR-2型红外辐射仪等手段对薄膜进行表征并研究不同工艺条件对薄膜红外性能的影响.结果显示,Al的掺杂并未改变ZnO的晶型结构,薄膜材料具有沿(002)晶面趋向性生长的特点.ZAO薄膜在可见光区具有高透过率,平均透过率在80%左右,在红外波段具有较高的透过率,所得到的ZAO薄膜在红外波段具有较低的发射率. 关键词:掺铝氧化锌; 红外辐射; 涂层材料; 掺杂半导体; Al-doped ZnO; infrared emissivity; coated materials; doped......
三水铝石的反应活性可能稍高;布居分析结果表明,三水铝石的H-O键和Al-O键的布居数最小,说明三水铝石较拜耳石和诺耳石H-O键和Al-O键的结合力最小,理论上三水铝石更有利于煅烧成氧化铝. 关键词:氢氧化铝;密度泛函理论;电子结构;布居分析 中图分类号:O 645 文献标识码:A Reactive ability and bond...=93.67?,β=118.92?,γ=70.27?. 图1 氢氧化铝晶体的计算模型 Fig.1 Calculation models of three kinds of Al(OH)3 crystals: (a) Gibbisite; (b) Bayerite; (c) Nordstradite 基于密度泛函理论(Density functional theory......
Separation efficiency of alumina particles in Al melt under high frequency magnetic field GUO Qing-tao(郭庆涛)1, CAO Zhi-qiang(曹志强)2, ZHANG Zhong-tao(张忠涛)2, LI Ting-ju(李廷举)2, JIN Jun-ze(金俊泽)2, HONG... and the separation efficiency is higher than 95%. The experimental results were compared with the calculated results at last. Key words: Al melt; alumina particles; electromagnetic separation; high......
Cathodic electrolysis method of depositing cerium conversion films on industrial pure aluminumZHANG Wei, LI Jiuqing, WU Yinshun, SHEN Defeng, and HE JianpingDepartment of Surface Science &..., respectively, have been developed to form cerium conversion films on the surface of industrial pure aluminum. The tested material was cathodically electrolyzed in the alkaline solution containing cerium......