Al 合金-Al_2O_3陶瓷粒子铸造复合材料是由硬质 Al_2O_3粒子在 Al 合金基体上均匀分散而构成.这种复合材料既有较高的硬度又有良好的塑性.尤其是与铝合金相比,其耐磨性有成倍提高.因而,这种材料可望用作耐磨、制动、防弹及遮蔽材料.由于...Al 合金-Al_2O_3陶瓷粒子铸造复合材料是由硬质 Al_2O_3粒子在 Al 合金基体上均匀分散而构成.这种复合材料既有较高的硬度又有良好的塑性.尤其是与铝合金相比,其耐磨性有成倍提高.因而,这种材料可望用作耐磨、制动、防弹及遮蔽材料.由于 Al 合金液与 Al_3O_3陶瓷粒子的润湿性很差,两者的比重也有较大差异,因此Al_2O_3粒子在 Al 合金液中受到很大斥力,极易聚合沉降.改善 Al_2O_3粒子与金属液润湿性的措施通常有下列四个方面:(1)颗粒表面包覆金属;(2)向金属液中加入合金元素;(3)粒子预处理;(4)超声波振动熔体。至于制备工艺,常见的有下列三种:(1)喷入法.利用喷枪,以惰性气体作载体。展开更多
Nanoparticles are increasingly being used to improve the friction and wear performance of polymers. In this study, we investigated the tribological behavior and energy dissipation characteristics of nano-Al_2O_3-reinf...Nanoparticles are increasingly being used to improve the friction and wear performance of polymers. In this study, we investigated the tribological behavior and energy dissipation characteristics of nano-Al_2O_3-reinforced polytetrafluoroethylenepolyphenylene sulfide(PTFE-PPS) composites in a sliding system. The tribological behaviors of the composites were evaluated under different normal loads(100–300 N) at a high linear velocity(2 m/s) using a block-on-ring tester. Addition of the nano-Al_2O_3 filler improved the antiwear performance of the PTFE-PPS composites, and the friction coefficient increased slightly. The lowest wear rate was obtained when the nano-Al_2O_3 content was 3%(volume fraction). Further, the results indicated a linear correlation between wear and the amount of energy dissipated, even though the wear mechanism changed with the nano-Al_2O_3 content, independent of the normal load applied.展开更多
文摘Al 合金-Al_2O_3陶瓷粒子铸造复合材料是由硬质 Al_2O_3粒子在 Al 合金基体上均匀分散而构成.这种复合材料既有较高的硬度又有良好的塑性.尤其是与铝合金相比,其耐磨性有成倍提高.因而,这种材料可望用作耐磨、制动、防弹及遮蔽材料.由于 Al 合金液与 Al_3O_3陶瓷粒子的润湿性很差,两者的比重也有较大差异,因此Al_2O_3粒子在 Al 合金液中受到很大斥力,极易聚合沉降.改善 Al_2O_3粒子与金属液润湿性的措施通常有下列四个方面:(1)颗粒表面包覆金属;(2)向金属液中加入合金元素;(3)粒子预处理;(4)超声波振动熔体。至于制备工艺,常见的有下列三种:(1)喷入法.利用喷枪,以惰性气体作载体。
文摘随着高速旋转机械材料的发展,对环氧树脂复合材料基体的性能提出了更高的要求.文章对相关的一种基体材料即环氧树脂/纳米氧化铝聚合物的制备工艺和性能进行研究.采用对纳米颗粒表面进行硅烷偶联处理和机械分散与超声波振动分散相结合的方法,实现了氧化铝纳米粒子在环氧树脂中的分散.经透射电镜(TEM)观察,改性后的纳米粒子能够较均匀地分散在环氧树脂中.并研究了溶液pH值、超声波分散时间对纳米粒子改性的影响,得出了最佳的工艺条件:溶液pH值为4～5,超声波分散时间为20 min.
基金Project(51165022)supported by the National Natural Science Foundation of ChinaProject(20122117)supported by the Lanzhou Science and Technology Bureau Foundation,ChinaProject(1310RJZA036)supported by the Natural Science Foundation of Gansu Province,China
文摘Nanoparticles are increasingly being used to improve the friction and wear performance of polymers. In this study, we investigated the tribological behavior and energy dissipation characteristics of nano-Al_2O_3-reinforced polytetrafluoroethylenepolyphenylene sulfide(PTFE-PPS) composites in a sliding system. The tribological behaviors of the composites were evaluated under different normal loads(100–300 N) at a high linear velocity(2 m/s) using a block-on-ring tester. Addition of the nano-Al_2O_3 filler improved the antiwear performance of the PTFE-PPS composites, and the friction coefficient increased slightly. The lowest wear rate was obtained when the nano-Al_2O_3 content was 3%(volume fraction). Further, the results indicated a linear correlation between wear and the amount of energy dissipated, even though the wear mechanism changed with the nano-Al_2O_3 content, independent of the normal load applied.
