To acquire a well bonded interface between the copper and the diamond particles in diamondcopper matrix composites, an available process to apply a vapor deposited aluminum（Al） coating onto diamond particles was use...To acquire a well bonded interface between the copper and the diamond particles in diamondcopper matrix composites, an available process to apply a vapor deposited aluminum（Al） coating onto diamond particles was used to solve this interfacial problem. The diamond-copper matrix composites were prepared by spark plasma sintering（SPS） process and the effect of Al-coated diamond particles was demonstrated. The experimental results showed that the densification, interfacial bonding and thermal conductivity of Al-coated composites were evidently improved compared to those of the uncoated composites. A maximum thermal conductivity（TC） of 565 W/（m·K） was obtained in the coated composite containing 50vol% diamond particles sintered at 1163 K. Additionally, the experimental data of thermal conductivity and coefficient of thermal expansion（CTE） were compared with the predictions from several theoretical models.展开更多
The surfaces of the veins of dragonflies(Pantala flavesens Fabricius and Crocothemis servilia Drury) wings are observed through SEM,and interesting micro and nano structures and morphologies are discovered.On the surf...The surfaces of the veins of dragonflies(Pantala flavesens Fabricius and Crocothemis servilia Drury) wings are observed through SEM,and interesting micro and nano structures and morphologies are discovered.On the surfaces of the veins,not only ripple wave morphologies are distributed,but also spikes are grown.Besides,on the surfaces of the spikes,straight stripe wave morphologies are grown along the generatrix.These marvelous micro and nano structures and morphologies may enable us to better understand the remarkable flying abilities of dragonflies.展开更多
基金Funded by the National Natural Science Foundation of China(21273192)the Foundation of He’nan Educational Committee(15B430009)the Key Scientific Research Foundation of Xuchang University(2014077)
文摘To acquire a well bonded interface between the copper and the diamond particles in diamondcopper matrix composites, an available process to apply a vapor deposited aluminum（Al） coating onto diamond particles was used to solve this interfacial problem. The diamond-copper matrix composites were prepared by spark plasma sintering（SPS） process and the effect of Al-coated diamond particles was demonstrated. The experimental results showed that the densification, interfacial bonding and thermal conductivity of Al-coated composites were evidently improved compared to those of the uncoated composites. A maximum thermal conductivity（TC） of 565 W/（m·K） was obtained in the coated composite containing 50vol% diamond particles sintered at 1163 K. Additionally, the experimental data of thermal conductivity and coefficient of thermal expansion（CTE） were compared with the predictions from several theoretical models.
基金supported by the National Natural Science Foundation of China (10872150,10872114)
文摘The surfaces of the veins of dragonflies(Pantala flavesens Fabricius and Crocothemis servilia Drury) wings are observed through SEM,and interesting micro and nano structures and morphologies are discovered.On the surfaces of the veins,not only ripple wave morphologies are distributed,but also spikes are grown.Besides,on the surfaces of the spikes,straight stripe wave morphologies are grown along the generatrix.These marvelous micro and nano structures and morphologies may enable us to better understand the remarkable flying abilities of dragonflies.
