S-shaped machining test has been proposed to ISO standard as an amendment to evaluate the accuracy of five-axis machine tools. However, as the geometric complexity of the S-shape machining test, it's very difficult to predict the influence of error sources on the S-shape machining accuracy. This study proposed a sensitivity analysis method to clarify the relationship between S-shaped machining accuracy and feed axes error motions. The results investigated that how each error motions influence S-shaped machining accuracy. This study could be a fundamental research to illustrate how the errors of feed drive system influence S-shaped machining accuracy.

This research aims to develop a pulse generator based on inductive voltage boosting method to meet the pulse requirements of electrical discharge machining. The method, which is a type of switching circuit using an inductor to store energy and low power DC power supply to offer energy, was applied to build the experimental platforms of electrical discharge machining and carry out machining in practice. The influences of parameters in open circuits and discharge states were investigated.

This paper describes the results of the detection and observation of arc column movement during inner-flushing EDM processes, which demonstrates that the arc columns, the dielectric fluid and the bubbles can interact with each other substantially. A hollow tool electrode was used to apply inner-flushing. Monopulse discharge and the resulting craters were observed. It is found that when the discharge current is constant, the length of the enlongated crater peaks at a certain flushing flow speed, which implies both the evaporation effect of arc columns to the fluid, and the cutting-off effect of the fluid against arc columns.

This paper investigates the relation between the occurrence of a type of short-circuiting and the machined surface quality in electrical discharge machining of carbon fiber reinforced plastics in order to get the good machined surface. The short-circuiting dealt with in this paper occurs when frayed carbon fibers on the machined surface come into contact with the tool electrode. Experimental results show that a period during which the short-circuiting doesn’t occur becomes longer as the machining depth becomes deeper. It was also found that the good machined surface which has few plucking of carbon fibers and deep pits can be obtained after the machining situation in which the short-circuiting has not occurred.

Nowadays, since metal constructions as the component of devices reduce down to nanoscale, the heat inhomogeneous caused by current dissipation is more obvious. In this research we study this phenomenon of electrical stimulated metal constructions to assist to design and maintain nanoscale devices. We utilize a home-made scanning near-field optical microscope (SNOM) to detect the thermally excited Terahertz waves (wavelength: between 8 μm and 25 μm) which are induced by the current dissipation in metal constructions. The SNOM is equipped with a highly sensitive Terahertz waves detector named CSIP (semiconductor charge-sensitive infrared phototransistor) which ensures the SNOM can probe thermally excited Terahertz waves with nanoscale spatial resolution without any external light source. In this study, we focus on narrow Nichrome (NiCr) constructions and detected diverse biased NiCr constructions’ current dissipation phenomenon by various level electrical stimulation at room temperature. We try to observe the current dissipation phenomenon directly and analyze the influential factors of current dissipation on NiCr construction. Meantime we consider the possibility of detecting current dissipation phenomenon on other electrical stimulated metal constructions.