如何提高90°弯头耐功率性能

分析了90°弯头的结构工艺特点及影响弯头耐功率性能的系统因素,提出两种改进方案,分别详述了两种改进方案的设计、实现及验证过程,在不增加外形尺寸、不改变接口尺寸、不影响互换性的情况下,低成本地实现了90°弯头耐功率性能的提高。     

金属基金刚石工具中胎体对金刚石的包镶能力

胎体对金刚石的包镶能力是影响金刚石工具使用寿命及加工性能的主要因素之一。本文分别综述了在孕镶金刚石工具和单层金刚石工具中,提高胎体对金刚石包镶能力的相关研究情况。孕镶金刚石工具的研究主要包括金刚石表面金属化、采用预合金粉末、添加微量稀土元素和强碳化物元素等;单层金刚石工具的研究则主要集中于钎焊单层金刚石工具。     

镁盐在制浆造纸工业中的应用

综述了镁盐在国内外造纸工业中的应用现状,阐述了我国造纸业合理开发利用镁资源的重要意义。     

Synthesis and application of a silica nanocomposite filler using water glass and a resole‐type phenol resin

Composite plastics in which silica was dispersed homogeneously were prepared from a resole‐type phenol resin and a silica‐sol using water glass. The silica (10–50 nm) was dispersed into resin particles of 2–20 μm in size. The powder that was obtained (nanocomposite filler) and a curing reagent were then mixed, and the resulting mixture was processed by using heat and pressure to yield plastics containing nanocomposite fillers. The coefficients of friction factor of the resulting plastics composites decreased by half and the amount of wear that they suffered decreased to just one tenth of that of the unfilled material, while their wear‐resistance was greatly improved. The new plastics displayed good sliding properties, while also maintaining good fluidity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

无机填料的表面处理及其在导热天然橡胶复合材料中的应用

用季戊四醇、丙三醇和钛酸酯偶联剂分别对氧化铝、氧化镁和高岭土进行表面改性,并将改性填料填充天然橡胶(NR)制备了导热复合材料,考察了表面处理剂种类及其用量对无机填料的影响,并研究了季戊四醇改性氧化铝填充NR复合材料的硫化特性、物理机械性能和导热性能.结果表明,3种填料中季戊四醇的改性效果最好,且其用量为1.0～1.5份时对氧化铝的改性效果最佳;随着改性氧化铝填充量的增加,复合材料的最大转矩、300%定伸应力、拉伸强度和热导率均增大,当其用量为60份时,改性氧化铝填充NR复合材料的热导率比未填充NR复合材料提高了23.9%.     

固化温度及填料对文物环氧胶粘剂性能的影响

研究了固化温度和填料对文物用双组分环氧胶粘剂力学性能的影响.红外分析表明,目前文物界普遍使用的国产3A万能胶,其主要组分为双酚A环氧树脂和脂肪胺/聚酰胺固化剂.以其作为研究对象,确定了适当的固化温度和填料用量,使环氧胶粘剂具有较好的操作性和粘接强度.     

不饱和聚酯型人造大理石的力学性能

简述了不饱和聚酯(UPR)型人造大理石的制备工艺。研究了质量比为4∶1的Al(OH)3/Ca(OH)2复合填料用量对不饱和聚酯型人造大理石力学性能的影响,对制得的人造大理石的耐腐蚀性进行了测试,采用光学显微镜观察了试样腐蚀前后的表面形貌。结果表明,在复合填料与UPR质量比为1.86∶1时,弯曲强度、压缩强度达到最大,分别为55.88 MPa和96.04 MPa。甲苯对人造石的腐蚀作用最大,氢氧化钠次之,硫酸腐蚀作用较小,腐蚀介质主要对不饱和树脂聚合物产生腐蚀,从而导致人造石力学性能降低。     

无溶剂环氧导静电涂料的研制

研制了一种无溶剂环氧导静电涂料,给出了该涂料的配方并测试了涂层性能.讨论了活性稀释剂、导电填料、颜料及浸泡介质对涂层导电率的影响.结果表明,该涂料安全环保,性能符合国标要求.     

基于两种丁腈橡胶复合填料的高性能离合器摩擦材料的研究

以丁腈胶乳改性水基酚醛树脂为胶粘剂,分别以玻璃纤维和复合包芯纱纤维为增强材料,采用两种新型丁腈复合填料[含9%硫化丁腈橡胶(NBR)和含20%未硫化NBR]为主要填料制备高性能离合器摩擦材料。实验结果表明,当m(9%硫化NBR)∶m(20%未硫化NBR)=1∶1[即W(NBR)≈16%]时,制取的摩擦材料具有良好的摩擦磨损性能、适中的硬度、良好的冲击强度和较低的噪音。     

Microstructure and shear strength of Mo-Cu/Cr18-Ni8 brazing joint in vacuum

High density Mo-Cu composite and Cr18-Ni8 stainless steel were brazed with Ag-Cu filler metal in vacuum of 10⁻⁵ Pa. The microstructure characteristics of Mo-Cu/Cr18-Ni8 brazed joint were investigated by field-emission scanning electron microscope (FESEM) with energy dispersive spectrometer (EDS) and shear strength was measured by shearing test. The results indicated that a Mo-Cu/Cr18-Ni8 joint with shear strength of 125 MPa was obtained at 940 °C for 20 min. There were Ag-Cu eutectic and Cu-rich phase without brittle intermetallic compounds formed in the joint. The shear fracture exhibited plastic feature with shear dimple and fracture located at the interface between braze seam and Cr18-Ni8 stainless steel.