Papers by Author: Cheng Guang Zhang

Abstract: According to this theory, the cavitation mechanism of ultrasonic-pulse electrochemical compound machining (UPECM) based on particle impact is proposed in the paper. The mechanism was studied particularly, and validated by experiments. The results show that ultrasonic cavitation promote pulse electrochemical compound machining, and particle impact has the catalysis of the anodic dissolution in the ultrasonic-pulse electrochemical compound machining. The results also indicate that the processing velocity can be improved under the particle impact, obtaining the surface quality in UPECM compound machining.

Abstract: The application of ultrasonic polishing and machining pulse electrochemical machining compound finishing is presented in the paper. The machining principle and experimental set-up of UPM-PECM compound finishing are introduced in the paper, discussing mechanism and model of the UPM-PECM in theory, and carrying on the experiment, which would co-act on hard-brittle metals in the machining. Furthermore, the material removal depth of UPM-PECM compound finishing is approximately proportional to the polishing time, and would decrease with the polishing time. This study indicates that machining velocity, machining accuracy and surface quality can be improved under UPM-PECM.

Abstract: The experiment of ultrasonic assisted pulse electrochemical compound finishing is carried in this paper. The machining principle of the compound finishing is discussed in this paper. Processing experiments of compound finishing are carried out to study the effects of the main processing para- meters, including the particle size, the ultrasonic vibration amplitude, the minimum gap between the tool head and workpiece and the pulse voltage, on the material removal rate and the surface quality for hard and brittle metal materials. The curves of the corresponding relationships are also obtained. The study indicates that the processing velocity, machining accuracy and surface quality can be improved under the compound finishing, obtaining the processing technology conductions of the compound finishing. Introductions

Abstract: The ZnSe thin films are co-deposited in the ZnSO4, Na2SeO3 and sodium citrate acidic solution, and the mechanism of the ultrasonic and pulse electrodeposition for ZnSe films is explained by the electrode-solution interface action model. Ultrasonic increases the activation energy of the [ZnCit]- and HSeO3 - and improves flow field of the solution between electrode and solution interface. The pulse current promotes the diffusion of solution and advantageously realizes the co-deposition of ZnSe films. The ZnSe thin films are pulse electrodeposited in zinc sulfate, selenite sodium and sodium citrate acidic solution with the action of ultrasonic. Finally, the ZnSe films have been characterized by the scanning electron microscope (SEM), the energy dispersion analysis of X-ray (EDAX) and X-ray diffraction (XRD).