Sub-micro spinel-structured LiMn1.5Ni0.5O4 material was prepared by a spray-drying method. The electrochemical properties of LiMn1.5Ni0.5O4 were investigated using Li ion model cells, Li/LiPF6 (EC+DMC)/LiMn1.5Ni0.5O4. It was found that the first reversible capacity was about 132 mAh g−1 in the voltage range of 3.60-4.95V. Ex situ X-ray diffraction (XRD) analysis had been used to characterize the first charge/discharge process of the LiMn1.5Ni0.5O4 electrode. The result suggested that the material configuration maintained invariability. At room temperature, on cycling in high-voltage range (4.50-4.95 V) and low-voltage range (3.60-4.50 V), the discharge capacity of the material was about 100 and 25 mAh g−1, respectively, and the spinel LiMn1.5Ni0.5O4 exhibited good cycle ability in both voltage ranges. However, at high temperature, the material showed different electrochemical characteristics. Excellent electrochemical performance and low material cost make this spinel compound an attractive cathode for advanced lithium ion batteries.

Amorphous carbon nanofiber arrays were synthesized in porous anodic aluminum oxide templates by pyrolysis of acetylene with cobalt nanoparticles as catalyst at 640 8C. The carbon nanofibers have amorphous structures under high-resolution transmission electron microscopy and Raman spectroscopy examination. The aligned amorphous carbon nanofibers grown within the pores of the aluminum oxide membranes are uniform with lengths of about 2μm and outer diameters of about 85 nm. The frictional properties of the array film of amorphous carbon nanofibers were investigated using an atomic force and friction force microscopy (AFM-FFM) and a ball-on-disk machine in air. The adhesion between the amorphous carbon nanofiber arrays and the anodic aluminum oxide membrane remained intact at relatively low loads. The AFM-FFM measurements indicated that the friction forces on the array film of amorphous carbon nanofibers were uniform. The array film had low friction coefficient and high wear resistance under the micro friction tests. The friction coefficient of the array film dry sliding against a corundum counterface was observed to be constant after an initial transient period and decreased with increasing the sliding velocity.

The slurry erosion-corrosion behaviour of TiN coated α-Ti alloy in aqueous silica slurry ontaining 3.5% NaCl has been investigated using a jet-in-slit rig. Erosion- orrosion tests were performed with slurry having jet velocity range 4.8-12.8 m s-1 and at normal impact angle. Because of synergistic effects between erosive wear and flow-induced corrosion, the erosion-corrosion rates of the TiN coating and a-Ti substrate were higher than the sum of erosive wear rates and flow-induced corrosion rates. At the lower slurry velocity, the TiN coating deposited on the a-Ti substrate presented better slurry erosion-corrosion resistance. With increasing slurry velocity, however, perforating, cracking and fragmenting of the hard TiN coating occurred and the protection effect of the coating layer reduced with the erosion-corrosion duration. And then the volume loss of the a-Ti substrate was enhanced through cracking of flakes induced by stress and corrosion.

The friction and wear behavior of peak aged Cu-Cr-Zr alloys dry sliding against a brass counterface were investigated on a pinon-disk wear tester. The microstructure of the aged Cu-Cr-Zr alloy before and after wear tests was analyzed by transmission electron microscopy. The worn surfaces of the Cu-Cr-Zr alloys were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy. The results indicated that an appropriate aging treatment resulted in the formation of fine, dispersive and coherent precipitates in the Cu matrix and thus could improve the hardness and wear resistance of the Cu-Cr-Zr alloy. The wear rate of the aged Cu-Cr-Zr alloy increased monotonically with increase of the normal load. With increasing sliding speed, the wear rate of the peak aged Cu -Cr-Zr alloy decreased initially and then began to increase. After reaching the maximum wear rate at a speed of 0.445ms-1, the wear rate decreased again with further increasing in the sliding speed. Adhesive wear and abrasive wear were the dominant wear mechanisms under unlubricated conditions.

Ni-P-carbon nanotube (CNT) composite coating and carbon nanotube/copper matrix composites were prepared by electroless plating and powder metallurgy techniques, respectively. The effects of CNTs on the tribological properties of these composites were evaluated. The results demonstrated that the Ni-P-CNT electroless composite coating exhibited higher wear resistance and lower friction coefficient than Ni-P-SiC and Ni-P-graphite composite coatings. After annealing at 673 K for 2 h, the wear resistance of the Ni-P-CNT composite coating was improved. Carbon nanotube/copper matrix composites revealed a lower wear rate and friction coefficient compared with pure copper, and their wear rates and friction coefficients showed a decreasing trend with increasing volume fraction of CNTs within the range from 0 to 12 vol.% due to the effects of the reinforcement and reduced friction of CNTs. The favorable effects of CNTs on the tribological properties are attributed to improved mechanical properties and unique topological struct ure of the hollow nanotubes.