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In order to achieve the goal of purifing the waste water and recycling of copper, use the electrodeposition to treat the copper-containing wastewater. The experiment studies the effects of electrode materials, cell voltage, plate distance, pH and other experimental conditions in the process of deposition and the effect of blowing nitrogen in the process of deposition. The results show that the best condition is using graphite-aluminum electrode, cell voltage is 7V, plate distance is 10mm and pH is 3 under the condition of blowing nitrogen. From which the removal rate of copper can reach more than 93%. Nitrogen can effectively reduce the concentration of dissolved oxygen in the water, reduce the degree of corrosion of the metal and eliminate the concentration polarization and electrochemical polarization in the deposition process to obtain a higher electrodeposition efficiency and current efficiency.

A 6061 aluminium rectangular tube extrusion using porthole dies was simulated by finite element software DEFORM-3D. The speed, stress, strain and temperature in the extrusion was given and analyzed. Using the original porthole die, the speed at the bearing entrance is not uniform. Bearing length at the rectangular corners should be increased. The stress, strain and temperature near the bearing are the largest, so the region of the die should be treated and enhanced.

Support structure of UAV (Unmanned Aerial Vehicle) engine is the important support for UAV engine, playing a support role and bearing extremely complex load, so its lightweight, strength and dynamic characteristics have a great influence on high performance of UAV. This paper focuses on UAV having the requirement of high performance and stability to the support structure of engine, and uses the software of MSC.Patran and MSC.Nastran and topology optimization criterion to lightweight design and analysis the support structure of UAV engine under the premise condition of existing constraints. Then the static strength and modal are analyzed for the result of lightweight design, and the strength of the model and dynamic characteristics are verified.

This paper explores the brazing process of SiCp/A356 composites and aluminum alloy using semisolid metal. The two substrates were heated up to the semisolid temperature range of Zn-Al filler metal in the joint region by a resistance heating plate. In order to mix the filler metal with the base metal of both sides to be a single uniform joint, a stirrer was introduced into the weld seam. After stirring, specimens were sectioned for analysis of macro- and micro-structures along the weld region. The research shows that SiCp/A356 composites and aluminum can be local joined with semi-solid filler metal. It can be found that part of the oxide film on the interface of the base metal was disrupted and removed through the observation by SEM. The metallurgical bonds can be formed between the filler metal and the base materials. Moreover, the oxide film of surface of aluminum alloy disrupted and removed was easier than that of surface of composites with existing of Sic particle. The joint microstructure with globular α-Al grain enclosed by rich-Zn phase can be obtained after stirring brazing.

How to prevent and delay the emergence of reflective cracks effectively is a most important task for road researchers to the asphalt mixture overlaid on the old cement concrete pavement. Several methods preventing reflective cracks prevention have been used before, but few are satisfied. In this paper Sampave is put forward as a new method or structure which is better than the others. Base on principle of reflective cracks, a new layer named Sampave was put forward. And this paper discusses its aspaht, gradation and performance. According to the requirement reasonable gradation is suggested for practice. By means of researching on materials performance in the lab, it is obviously that Sampave has good performance at low temperature. Results of bending and creep test indicate that Sampave has good ability in resisting deformation. Meanwhile the result of fatigue test indicates that the fatigue life of Sampave is more than 210 thousand, therefore it has good performance in anti-cracking, and also the results of application in the project show its advantages in resisting reflective cracks.