With 2 kW continuous wave Nd-YAG laser, SiC ceramic powder was laser-cladded on the AA6061 aluminium alloy surface. Within the range of process parameters investigated, the parameters were optimized to produce the SiC...With 2 kW continuous wave Nd-YAG laser, SiC ceramic powder was laser-cladded on the AA6061 aluminium alloy surface. Within the range of process parameters investigated, the parameters were optimized to produce the SiC_p reinforced metal matrix composites(MMC) modified layer on AA6061 alloy surface. After being treated, the modified layer is crack-free, porosity-free, and has good metallurgical bond with the substrate. The microstructure and chemical composition of the modified layer were analyzed by such detection devices as scanning electronic microscope(SEM-EDX) and X-ray diffractometer(XRD). The performance of electrochemical corrosion and cavitation erosion and their mechanism were estimated by the microhardness tester, potentiostat and (ultrasonic-)(induced) cavitation device.展开更多
Sessile drop technique was used to investigate the influence of Ti on the wetting behaviour of copper alloy on SiC substrate. A low contact angle of 15- for Cu alloy on SiC substrate is obtained at the temperature of ...Sessile drop technique was used to investigate the influence of Ti on the wetting behaviour of copper alloy on SiC substrate. A low contact angle of 15- for Cu alloy on SiC substrate is obtained at the temperature of 1 100 ℃. The interfacial energy is lowered by the segregation of Ti and the formation of reaction product TiC, resulting in the significant enhancement of wettability. Ti is found to almost completely segregate to Cu/SiC interface. This agrees well with a coverage of 99.8%Ti at the Cu/SiC interface predicted from a simple model based on Gibbs adsorption isotherm. SiCp/Cu composites are produced by pressureless infiltration of copper alloy into Ti-activated SiC preform. The volume fraction of SiC reaches 57%. The densification achieves 97.5%. The bending strength varies from 150 MPa to 250 MPa and increases with decreasing particle size.展开更多
基金Project(2002AA305203) supported by Hi tech Research and Development Program of China Project(20031024) suppor ted by Liaoning Scientific and Technological Development Foundation Project(2004D011) supported by Liaoning Educational CommitteeResearch
文摘With 2 kW continuous wave Nd-YAG laser, SiC ceramic powder was laser-cladded on the AA6061 aluminium alloy surface. Within the range of process parameters investigated, the parameters were optimized to produce the SiC_p reinforced metal matrix composites(MMC) modified layer on AA6061 alloy surface. After being treated, the modified layer is crack-free, porosity-free, and has good metallurgical bond with the substrate. The microstructure and chemical composition of the modified layer were analyzed by such detection devices as scanning electronic microscope(SEM-EDX) and X-ray diffractometer(XRD). The performance of electrochemical corrosion and cavitation erosion and their mechanism were estimated by the microhardness tester, potentiostat and (ultrasonic-)(induced) cavitation device.
基金Project(2006AA03Z557) supported by The High-tech Research and Development Program of ChinaProject(2006CB605207) supported by the National Basic Research Program of ChinaProject(I2P407) supported by MOE Program For Changjiang Scholars and Innovative Research Team in University
文摘Sessile drop technique was used to investigate the influence of Ti on the wetting behaviour of copper alloy on SiC substrate. A low contact angle of 15- for Cu alloy on SiC substrate is obtained at the temperature of 1 100 ℃. The interfacial energy is lowered by the segregation of Ti and the formation of reaction product TiC, resulting in the significant enhancement of wettability. Ti is found to almost completely segregate to Cu/SiC interface. This agrees well with a coverage of 99.8%Ti at the Cu/SiC interface predicted from a simple model based on Gibbs adsorption isotherm. SiCp/Cu composites are produced by pressureless infiltration of copper alloy into Ti-activated SiC preform. The volume fraction of SiC reaches 57%. The densification achieves 97.5%. The bending strength varies from 150 MPa to 250 MPa and increases with decreasing particle size.
