This paper presents a compact method to predict the amplitude displacement and evaluate the influence of flexure structure on the vibration-assisted micro-milling device.The voltage load and flexure dimension variation are applied to the Finite Element model to obtain the predicted amplitude displacement. The simulation results show that amplitude displacement increases linearly along with the voltage load, but the influence of flexure thickness shows a varying trend on the amplitude displacement. The method can predict the device's amplitude displacement and movement pattern and is suitable for determining the optimum design for the vibration-assisted micro-milling device.
The application of pyrolysis for the thermal decomposition of tire waste can be taken as the ideal concept to reduce and recycle tire waste. The product of the process can produce condensate oil, a typical oil that is close to crude oil properties. The critical aspect of the pyrolysis process is the design of the reactor, particularly for the condenser where the rate of heat transfer contributes to the overall quality and quantity of the produced condensate oil. This study focused on the effect of water flow direction on the condensation process of pyrolysis gas. The quantity and quality of the produced oil are examined to observe the effect of the condensation process. Two different water flow directions are tested in the process, namely, counter flow and parallel flow direction. The effect of water flow direction in the condenser clearly affects the pyrolysis process to produce the condensate oil. Based on the production quantity, the counter flow condenser is able to produce 355 ml of condensate oil while the parallel flow one merely 290 ml. Based on the quality of the produced condensate oil, the counter flow condenser is generally better than the parallel flow one where the density, flash point and viscosity are close to crude oil properties. The rate of heat transfer from the condenser to the pyrolysis gas is the main factor that contributes to the quality and quantity of the condensate oil. The average heat transfer for the counter and parallel flow is 2,728 W and 1,865 W, respectively. It can be said that using the counter flow condenser for the pyrolysis reactor can improve the quality and quantity of the condensate oil
Vibration assisted machining (VAM) is one of the hybrid machining processes for improving the machined surface quality. VAM performance is mainly influenced by the combination of machining and vibration control parameters, where surface roughness value (Ra) became the benchmarking indicator. It is difficult to determine the optimum parameter combination to produce high precision products, especially for micro-milling, due to the interconnected correlation among parameters. The benefits of high-speed machining with VAM are high material removal rate and shorter machining time than low-speed machining. VAM operation at high-speed machining is still limited due to the high possibility of chatter occurrence. Therefore, this research aims to evaluate the 2D VAM resonant performance at low-speed and high-speed machining, operated at ultrasonic vibration and amplitude below one μm. The mathematical model and experimental evaluate the vibration effect based on machining mode, amplitude, and spindle speed variation. The mathematical modelling and experiment result complement each other, where the mathematical model can characterize the effect of resonant vibration, amplitude, and spindle speed increment on the tool path trajectory. The 2D resonant vibration at the feed direction causes interrupting cutting and transforms the tool path trajectory from linear to wavy. The mathematical model and experiment result show the dominant influence of spindle speed and feed rate on the toolpath trajectory and Ra, where low spindle speed and feed rate result in better machine surface roughness. The low-speed machining with VAM results in Ra value between 0.1–0.155 μm, which is below the high-speed machining result, between 0.2–0.38 μm
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.