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The transformation temperature and time of α+γ2 to ß in a Cu-Al alloy after cryogenic treatment during heating were measured by DSC, and the transformation activation energy of α+γ2 to ß was also calculated. It is indicated that the Cu-Al alloy with heating rate of 10℃/min, the phase transformation onset and ending temperature is 561.75℃ and 582.88℃, respectively, and the phase transformation time is126.6S. The phase transformation activation energy decreases with the increasing volume fraction of their phase transformation.

Precursor of tungsten was obtained by spray drying process with high purity APT crystal liquor as material. The precursor was analysized by electron microscopy and X-ray. A suitable spray drying process was found through the morphology and powder structure. The influence of atomization disk rotational speed, the concentration ratio of ammonia to WO3 in APT liquor and APT liquor’s concentration on particle size, structure and morphology of the ball precursor were studied. Uniformity superfine WO3 was obtained from precursor by calcined.

B4C ceramic nozzle was produced by hot pressing, and wear behavior of the nozzle by SiC, white emery and umber emery abrasives were investigated, erosion wear mechanisms based on stress states analyzing with finite element method were studied. Results showed that the greater the hardness and grit size of abrasives, the more mess loss of the nozzle, the maximum stress appeared in entrance area of the nozzle and minimum stress in middle area, while the stress of exit area was lower than entrance area and higher than middle area. The nozzle exhibited a brittle fracture induced removal process in the entrance of the nozzle and a stress fatigue induced removal process in the middle of the nozzle under the condition of SiC abrasives impacting, and a stress fatigue induced removal process under white and umber emery abrasives impacting.

The influence of deformation on dechromization of CuCr alloy in H3PO4 solutions was investigated by static immersion corrosion tests. The properties of undeformed and deformed alloys were characterised by XRD, Metallograph, SEM and X-ray fluorescence spectrometer respectively. It is observed that the deformation plays an important role in dechromization of CuCr alloys in H3PO4 solutions. Compared with undeformed one, the deformed CuCr alloy’s incubation time of corrosion is shortened, the concentration and temperature of H3PO4 solutions needed for dechromization decrease. Consequently the tendency of dechromization increases. Surface analysis showed that the microstructure of the dechromization layer is scarcely influenced. Finally, the dechromisation mechanism was discussed.

The electrochemical compatibility between natural graphite and garnet-like Li6BaLa2Ta2O12 or organic electrolytes was investigated. The formation of solid electrolyte interface (SEI) films in the initial cycle was investigated by galvanostatic charge and discharge, cyclic voltammetry experiments. The experimental results show that electrochemical compatibility between natural graphite and Li6BaLa2Ta2O12 is the most excellent, while electrochemical compatibility between natural graphite and PC-based electrolytes are the poorest. In the initial cycle, the discharge capacity and charge-discharge efficiency are both the highest in Li6BaLa2Ta2O12 electrolyte, and they are 337.1 mAhg-1 and 99.5 %, respectively.

Ni/Al2O3 composite coatings were prepared by direct current (DC), single pulse current (PC) and pulse reversal current (PRC), respectively. The hardness and wear resistance of the coatings were investigated and the morphology and elements distribution in cross-section were analyzed by the application of SEM/EDS, XRF and XRD equipped with stress measuring device. The results show that the hardness of the three kinds of coatings increase with increasing Al2O3 content. The coating prepared by PRC plating exhibits higher hardness and better wear resistance, while that of DC plating has lower hardness and poorer wear resistance. The higher hardness and better wear resistance of coating of PRC plating can be ascribed to fine microstructure and weaker stress between substrate and coatings.