Papers by Keyword: Nanoprecision Machining

Abstract: This paper describes machining characteristics of high spindle speed WEDG using the electrostatic induction feeding method. In this method, non-contact electric feeding allows the workpiece rod to be rotated at a high speed of up to 50000rpm. Since the temperature rise on the workpiece surface is low, the material removal rate was two times higher and the surface roughness was also improved compared to the normal RC discharge circuit where the rotational speed was 1000rpm at the highest due to contact electric feeding using a brush. Furthermore, micro rods thus prepared were used as tool electrodes to machine micro-holes with the same rotation speed of 50000rpm. It was found that smaller gaps and better straightness can be obtained due to the high flushing efficiency at the high spindle speed.

Abstract: The finishing process of a metal mold depends on the hand work of experts by using a whetstone tool in many cases. This is because it is difficult to treat the three-dimensional configuration, such as free-form surfaces and convex and concave configurations. To overcome this difficulty, we propose a dynamic magnetic field assisted finishing using magnetic compound fluid (MCF) for three-dimensional configurations. In this paper, we demonstrate the MCF slurry (MCF mixed abrasive and cellulose fiber in) under dynamic magnetic field shows the high form restoration and generates the high normal force compared to that under static magnetic field; resulting in shows the high finishing performance. Moreover, we compare and discuss the surface roughness and form accuracy under both static and dynamic magnetic fields against three-dimensional configuration made of high hardness non-ferrous mold steel HPM75, which is used for plastic injection mold.

Abstract: Nano-precision machining using focused ion beam (FIB) is widely applied in many fields. So far, FIB-based nanofabrication for specific nanoscale applications has become an interesting topic to realize more diversities for nano-construction. Through FIB machining, we can easily achieve the required nano- and micro-scale patterning, device fabrication, and preparation of experimental samples. Nowadays, there is an increasing trend to learn from nature to design novel multi-functional materials and devices. Thus, more interestingly, another advantage of FIB is that it can be conveniently used to analyze the natural photonic structures, e.g., those in the butterfly which exhibits amazing optical phenomena due to sub-wavelength structural color. Accordingly, in the present study, structural analyses for butterfly wings were carried out using FIB. It is found that the photonic structures for the backside and frontside of the butterfly wing studied differ considerably. The difference accounts for the different colors on the dorsal and ventral sides of butterfly wings.

Abstract: The copying characteristic of the tool motion on the workpiece profiles is investigated. Assuming that the workpiece profile consists of sinusoidal-wave components, the amplitude ratio between the workpiece profile and the tool motion is defined as copying rate . An experiment was conducted to identify in shaping of electroless plated nickel. With polycrystalline diamond tools, the copying rate was obtained as =1.16. The result indicates that the amplitude of the workpiece profile can be larger than that of the tool motion. Shaping of slot profiles was carried out to investigate the influences of depth of cut, rake angle and relief angle on the copying characteristic. The depth of slot was larger than the tool displacement in the Z-direction by 0.1-0.4 μm when the rake angle was -5 degrees and the relief angle was 12 degrees.

Abstract: Nanoscience and nanotechnology is one of the most important researches in the 21st century. This paper took the application of nanotechnology for mechanical manufacturing as a point of departure, discussed the nano-material technology, nano-processing technology, nano-assembly technology and nano-measurement technology in mechanical manufacturing, and described the resulting theory nano-mechanics which was different from the traditional mechanics. Moreover the important role of nano-technology for the development of mechanical manufacturing was pointed out at the end of the paper.

Abstract: A completely new diamond wheel, named the 3R wheel, has been developed. The 3R wheel has three unprecedented functions, reconfiguration, restoration and recyclability, and is molded from a mixture of special thermoplastic resin filler and diamond powder. The concept of the 3R wheel is to control the quantity and the position of abrasive material by actively using heat. In this study, tungsten carbide (WC) was ground using a thermoplastic resin bonded diamond wheels (radius 1.4 mm) with three different concentrations of 1500 grain size abrasive. As a result, a grinding ratio of over 200 and 18 nmRa roughness was achieved without dressing. In addition, a large quantity of abrasives was confirmed on the wheel surface by observation.