We present a method to fabricate superhydrophobic surfaces on copper substrate using reciprocating type high speed wire cut electrical discharge machining (HS-WEDM) and self-assembly technology. Herein, single factor experiment was used to investigate the influence of several major parameters of the wire electrical discharge machining processing, such as pulse width, pulse gap (pulse interval) and power tube, on the contact angle of resulting surface. Results show that a composite structure, composed of craters and projections, is fabricated on the copper surface, which is the key reason of superhydrophobicity. With the change of pulse width, pulse interval, and the number of the power tube, the hydrophobic properties of resulting copper surface was changed. This paper provided the theoretical support for industrialized fabrications of super-hydrophobic brass surface.

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A non-smooth surface with convex domes was fabricated on a chemical polished 2024 aluminum alloy substrate using the method of pressing with a symmetrically distributed concave hole module. Anode oxidation technique was used to prepare alumina films on a non-smooth surface. The as-prepared surfaces possessing microscale morphology and multiscale structures without anything chemical modification exhibited excellent hydrophobicity, and had a maximum water contact angle of about 133o. The microscale morphology of the non-smooth alumina films were investigated by a stereo microscope and a laser scanning confocal microscopy. A scanning electron microscopy was used for surface corresponding microstructure of the non-smooth alumina films. The forming course of the alumina films with pores was analyzed. Such an alumina films that combine excellent hydrophobicity with other properties may have many potential applications.

In view of the deficiencies of current inspection methods on high-voltage transmission lines, the paper introduces a kind of inspection robot from two parts of mechanical structure and control system. A three-arm structure is adopted in the mechanical structure, while the control system is composed of the supervisory control subsystem on the ground and the body control subsystem. The PC/104 and AT89S52 are used for the master controller and control chip, and the BLDC is used for the power drive component. Through the simulation analysis by Matlab/Simulink, the anti-interference performance and speed control performance of the walking wheel motor control system is explored. Besides, conclusion that the walking wheel motor control system meets the requirement of speed is drawn.

Ultra-smooth optical surfaces are very important in widely fields. They’re not only used in optics, but also in the electronics. Ultra-smooth surfaces are difficult to process, because the rms is less than 1nm. The process methods have Teflon Polishing, Float Polishing (FP), Magnetorheological Finishing (MRF) and Ion Beam Figuring (IBF) etc. Compared with conventional polishing, IBF have higher processing quality and efficiency. Low-energy (<2Kev) IBF can form the self-organized nanopatterns on optical surfaces. Since IBF is a non-contact method; there is no edge effect during the process. We can change the ion beam parameters to get dot or ripple pattern on substrate. Only the self-organized ripple pattern is discussed in the paper. For the prediction of process parameters, the principle theories Sigmund theory and BH model are used the interplay between the angle of ion beam incidence, ion flux, incident energy and substrate temperature leads to the self-assembly, which are considered by these theory. In this paper the angle of incidence and incident energy are mainly researched on. Processing nanopatterns on Si has been simulated by SRIM program with these theory and the results reveal several laws in the process. It is believed that these laws will help us to well predict the ion beam parameters and lead IBE experiments.