Four kinds of Cu-based composites with different mass ratios of graphite and WS2 as lubricants were fabricated by hot-pressing method. Electrical sliding wear behaviors of the composites were investigated using a bloc...Four kinds of Cu-based composites with different mass ratios of graphite and WS2 as lubricants were fabricated by hot-pressing method. Electrical sliding wear behaviors of the composites were investigated using a block-on-ring tribometer rubbing against Cu-5%Ag alloy ring. The results demonstrated that 800 ~C was the optimum sintering temperature for Cu-graphite-WS2 dual-lubricant composites to obtain the best comprehensive properties of mechanical strength and lubrication performance. Contact voltage drops of the Cu-based composites increased with increasing the mass ratio of WS2 to graphite. The Cu-based composite with 20% graphite and 10% WS2 showed the best wear resistance due to the excellent synergetic lubricating effect of graphite and WS2. The reasonable addition of WS2 into the Cu-graphite composite can remarkably improve the wear resistance without much rise of electrical energy loss which provides a novel principle of designing suitable sliding electrical contact materials for industrial applications.展开更多
The mechanical properties and microstructures of Al_(2)O_(3)whiskers and graphene nano-platelets(GNPs)co-reinforced Cu-matrix composites were studied.Cu-matrix composites with a variation of GNPs amount were fabricate...The mechanical properties and microstructures of Al_(2)O_(3)whiskers and graphene nano-platelets(GNPs)co-reinforced Cu-matrix composites were studied.Cu-matrix composites with a variation of GNPs amount were fabricated by mechanical alloying followed by vacuum hot-pressing sintering and hot isostatic pressing.The Cu-matrix composite with 0.5 wt.%GNPs(GNPs-0.5)suggests a good interfacial bonding of both Cu/C and Cu/Al_(2)O_(3)interfaces.Both the hardness and compressive strength of Cu-matrix composites show a consistent tendency that firstly increases to a critical value and then decreases with increasing GNPs amount.It is suggested that the most possible strengthening mechanisms of both GNPs and Al_(2)O_(3)whisker working in the Cu-matrix composites involve energy dissipating and load transfer,as well as grain refinements for GNPs.The synergetic effect of GNPs and Al_(2)O_(3)whiskers is highlighted that the embedded GNPs would hinder the crack path generated at the Al_(2)O_(3)/Cu interface and enhance the already outstanding strengthening effect that Al_(2)O_(3)whiskers provide.展开更多
基金Projects(9102601860979017) supported by the National Natural Science Foundation of ChinaProject(20110111110015) supported by the Doctoral Fund of Ministry of Education of China
文摘Four kinds of Cu-based composites with different mass ratios of graphite and WS2 as lubricants were fabricated by hot-pressing method. Electrical sliding wear behaviors of the composites were investigated using a block-on-ring tribometer rubbing against Cu-5%Ag alloy ring. The results demonstrated that 800 ~C was the optimum sintering temperature for Cu-graphite-WS2 dual-lubricant composites to obtain the best comprehensive properties of mechanical strength and lubrication performance. Contact voltage drops of the Cu-based composites increased with increasing the mass ratio of WS2 to graphite. The Cu-based composite with 20% graphite and 10% WS2 showed the best wear resistance due to the excellent synergetic lubricating effect of graphite and WS2. The reasonable addition of WS2 into the Cu-graphite composite can remarkably improve the wear resistance without much rise of electrical energy loss which provides a novel principle of designing suitable sliding electrical contact materials for industrial applications.
基金the financial supports from the National Natural Science Foundation of China (No. 52101183)China Postdoctoral Science Foundation (Nos. 2017M623054, 2018T110993)
文摘The mechanical properties and microstructures of Al_(2)O_(3)whiskers and graphene nano-platelets(GNPs)co-reinforced Cu-matrix composites were studied.Cu-matrix composites with a variation of GNPs amount were fabricated by mechanical alloying followed by vacuum hot-pressing sintering and hot isostatic pressing.The Cu-matrix composite with 0.5 wt.%GNPs(GNPs-0.5)suggests a good interfacial bonding of both Cu/C and Cu/Al_(2)O_(3)interfaces.Both the hardness and compressive strength of Cu-matrix composites show a consistent tendency that firstly increases to a critical value and then decreases with increasing GNPs amount.It is suggested that the most possible strengthening mechanisms of both GNPs and Al_(2)O_(3)whisker working in the Cu-matrix composites involve energy dissipating and load transfer,as well as grain refinements for GNPs.The synergetic effect of GNPs and Al_(2)O_(3)whiskers is highlighted that the embedded GNPs would hinder the crack path generated at the Al_(2)O_(3)/Cu interface and enhance the already outstanding strengthening effect that Al_(2)O_(3)whiskers provide.
