In this paper, the high-speed clinching named electromagnetic-driven clinching (EMDC) method was adopted and analyzed by experiment, numerical simulation and theoretical calculation. The deformation behavior and mechanical properties of 5052-O EMDC joints have been investigated. The result showed that the punch speed can reach 3 m/s, The maximum strain rate of the EMDC process can reach 6000 s−1. The EMDC process can be divided into deep drawing, interlocking, and unloading stages. The neck thickness tN changes mainly in deep drawing stage. The interlock value tU changes mainly in interlocking stage. The discharge voltage level can precisely control the formation of the joint. With the increase of the discharge voltage, the tN did not change significantly, while the tU increased and mechanical properties of the joint gradually improved. When the discharge voltage was 3.4 kV, the shear and tensile joint strength were 1571 N and 746 N, respectively. The simulation results and the theoretical calculations were in good agreement with the experimental results.
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Al doped ZnO (AZO) thin films were prepared on silica substrates by sol-gel method. The films showed a hexagonal wurtzite structure with a preferred orientation along c-axis. Suitable Al doping dramatically improved the crystal quality compared to the undoped ZnO films. Dependent on the Al dopant concentration, the diffraction peak of (0 0 2) plane in XRD spectra showed at first right-shifting and then left-shifting, which was attributed to the change in defect concentration induced by the Al dopant. Photocatalytic properties of the AZO film were characterized by degradation of methyl orange (MO) under simulated solar light. The transmittance of the films was enhanced by the Al doping, and the maximum transmittance of 80 % in the visible region was observed in the sample with Al concentration of 1.5 at.% (mole fraction). The film with 1.5 at.% Al doping achieved also maximum photocatalytic activity of 68.6 % under solar light. The changes in the film parameters can be attributed to the variation in defect concentration induced by different Al doping content.
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