Papers by Author: T.M. Yue

Abstract: A three-layer Ti-Si graded coating was fabricated on a commercially pure titanium substrate by laser cladding with Ti-5.8 at%Si, Ti-9.0 at%Si and Ti-13.5 at%Si mixed powders. The microstructure of the three layers comprised Ti-Si solid solutions (Ti) and the Ti₅Si₃ compound. As the silicon content was increased, the microstructure along the direction of deposition underwent a series of changes, including replacement of the (Ti) phase by the primary Ti₅Si₃ phase, and a change of the (Ti)/Ti₅Si₃ eutectic growth from lamellar to anomalous.

Abstract: A new concavo-convex electrode has been designed and employed. And an analysis of the electrical discharge machining (EDM) mechanism of a particulate reinforced metal matrix composite with this new electrode was conducted in this study. It was found that EDM with this new electrode can accelerate the debris discharge during machining so that it has a higher MRR compared to the case where a normal electrode was employed. Moreover, by studying the surface craters, it could confirm that discharge craters tend to connect together for the normal electrode. This indicates an abnormal arcing condition. Thus, the wire electrode was easy to be broken. While for the new electrode, separated craters were observed on the machined surface. This means a stable processing condition. The experiment results reveal the processing mechanism of EDM electrical discharge machining of MMCs by employing this new electrode.

Abstract: A new concavo-convex electrode has been designed and fabricated. And an analysis of the electrical discharge machining (EDM) of a particulate reinforced metal matrix composite this new electrode was conducted in this study. The material removal rate (MRR) of new electrode and normal electrode are compared in different applied voltage and duty cycle conditions. It was found that EDM with this new electrode can accelerate the debris discharge during machining so that it has a higher MRR compared to the case where a normal electrode was employed. Moreover, by studying the waveforms, it could confirm that a stable processing condition can be obtained by employing the new electrode. The experiment results reveal that it is a feasible and effective way to machine MMCs by employing this new electrode.

Abstract: The influences of ultrasonic field to polishing performance of Polishing Based on Coupling Vibration of Liquid (PCVL) are analyzed here. The simulation results shows that sound field in the original polishing device is rather uneven due to the existence of standing wave. To obtain better polishing performance, the experimental equipment was modified. Uniformity of the sound field was improved by preventing standing wave, thus a better surface quality could be achieved. Furthermore, a higher machining efficiency could be also obtained because sound intensity was strengthened at the same time. From the results serials of experiments, the improvements made by modified equipment are clearly shown.

Abstract: Experiment research of polishing based on liquid two-dimension vibration is carried out by a vibrating device which is driven by ultrasonic source and can produce coupling vibrations of liquid. Sound pressures of some key points in water are tested by hydrophone and translated into sound intensity to evaluate the effect of input voltage of transducer. It is analyzed which vibration state of fluid field and the way that workpiece is clamped is the best for the polishing. Polishing results of quartz glass are evaluated by the use of region-track measure method, and some polishing rules are presented.

Abstract: A novel polishing technique based on the two-dimension vibration of fluid is put forward to obtain ultra-smooth surface without damage. In operation, the polishing pad is replaced by fluid where fine abrasive particles are mixed, and the impact and grinding effect can be produced by means of the vibration of fluid and the relative motion of workpiece. It can achieve the ultra-precise polishing for all kinds of planes and curved surfaces. A finite element method is employed to analyze the dynamic behaviors, including vibration mode and harmonic response under the action of the exciter, and the fluid field based on two-dimension vibration is simulated.