• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.623-624
• /
• 2005

Micro injection molding is a branch of micro system technology and has been under development for the mass manufacture of micro parts. Enhanced technological products like micro optical devices are entering the market. This paper presents fundamental research on the injection molding technique in micro fabrication. In order to successful manufacturing of micro plastic parts, it is necessary to research for development of micro-injection machine, machining of micro mold, decision of optimum injection conditions and the research for polymer material. Therefore in this study, in order to machining of micro mold, a mold core with microscopic V-shaped groove was tooled by ultra-precise tooling machine. The transcription experiments with a polymer, PMMA resin on the surface of core with Ni plating were carried out and surface profile of injected parts was measured with AFM.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.5
• /
• pp.38-45
• /
• 2004

As optical communication is being substituted for telecommunication, the demand of a large variety of fiber optic components is increasing. V-groove substrates, one of the module components, are used to connect optical fibers to optical planar circuits and to arrange fibers. Their applications are multi-channel optical connectors and optical waveguide fiber coupling, etc. Because these substrates are a critical part of the splitter in a multiplexer and a multi fiber connector, precise and reliable fabrication process is required. For precisely aligning core pitch between fibers, machined core pitch tolerance should be within sub-microns. Therefore, these are generally produced by state-of-the-art micro-fabrication like MEMS. However, most of the process equipment is very expensive. It is also difficult to change the process line for custom designs to meet specific requirements using various materials. For various design specifications such as different values of the V angle and low-priced process, the fabrication method should be flexible and low cost. To achieve this goal, we have suggested a miniaturized machine tool with high accuracy positioning system. Through this study, it is shown that this cutting process can be applied to produce V-groove subtracts. We also show the possibility of using a miniaturized machining system for producing small parts.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.97-100
• /
• 2004

In recent years, a demand for micro-structure machining is increasing by the development of information and optics industries. Micro machining technology is in general well known in the field of lithograghy. However, the requirement of producing micro machine and/or micro mechanism with metal materials will be increased since a variety of workpiece configurations can be easily made. In this paper, ultra precision machine is developed to obtain micro groove and mirror surface using single crystal diamond tool. According to the cutting experiment, no burr was found at the edge of V-grooves, and the surface roughness of copper is about 1～3nm Ra. It is verified that ultra precision machine is effective to high precision machining.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.725-726
• /
• 2008

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.3
• /
• pp.218-223
• /
• 2009

The micro pattern machining on the surface of wide mold is not easy to be simulated by conventional software. In this paper, a software is developed for micro pattern cutting simulation. The 3d geometry of v-groove, rectangular groove, pyramid and pillar patterns are visualized by C++ and OpenGL library. The micro cutting force is also simulated for each pattern.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.542-546
• /
• 2003

This paper describes the machining characteristics of a developed micro grooving machine. Experiments have been conducted on the various grooving condition such as spindle revolution speed, feed rates and depth of groove. V and U-shaped blade tool and STD11 workpiece was used in this study. Evaluating the machining conditions, RMS and frequency spectrum analysis of AE(acoustic emission) signals according to each conditions were applied. As a result, this study presented the process to optimize micro grooving condition and possibility of application of AE technique in groove machining.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.12 no.4
• /
• pp.23-28
• /
• 2003

This paper describes the machining characteristics of a developed micro grooving machine. Experiments have been conducted on the various grooving condition such as spindle revolution speed, feed rate and depth of groove. V and U-shaped blade tool and STD11 workpiece was used in this study. To evaluate the developed micro grooving machine, AE signal obtained from each experimental condition was analyzed, and cutting stability was compared with the surface state. As a result this study presented the process to optimize grooving condition and possibility of application of AE technique in groove machining.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.10a
• /
• pp.407-408
• /
• 2006

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.20 no.5
• /
• pp.523-527
• /
• 2011

Polycarbonate (PC) polymer is an engineering plastic which has large tensile strength and impact resistance and is wildly used as functional parts like micro mold. Direct machining of PC materials produces lots of burrs and rough surface due to large ductility and weak heat resistance and hence it is very difficult to machine PC materials using cutting tool to make micro-parts. In this study, elliptical vibration cutting (EVC) or 2-dimensional vibration cutting was performed to minimize the size of micro V-grooves on PC material. From the experimental results, it was observed that as the cutting depth and pattern size become smaller, the better machining quality was obtained, which is attributed to the positive effect of EVC that is dependent on the ratio of vibration amplitude to cutting depth. As the height of V-groove becomes less than $1.8{\mu}m$, however, the machining quality becomes lower as the pattern size decreases.

• Transactions of Materials Processing
• /
• v.14 no.5 s.77
• /
• pp.432-438
• /
• 2005

Among the most of manufacturing process, plastic deformation method offers a significant advantage in productivity and enable mass production with controlled quality and low cost. From the point of view, micro forming is a well suited technology in manufacturing very small metallic parts, in particular for mass production, as they are required in many industrial products. Meanwhile, Al 5083 superplastic alloy with very small grains has a great advantage in achieving micro deformation under low stress due to its relatively low strength at a specific high temperature range. This paper describes the micro formability of Al 5083 superplastic alloy and its application to die forging of micro patterns. Micro formability tests of Al 5083 superplastic alloy were carried out with the specially designed micro forging system by using V-grooved micro dies and pyramidal dies made of (100) silicon. With these dies, micro forging was conducted by varying the applied load, material temperature and forging time The micro formability of Al 5083 superplastic alloy was evaluated by comparing $R_f$ value, where $R_f\;=\;A_f/A_v$ ($A_v$ : cross-sectional area of the flowed metal, $A_v$ : cross sectional area of V-groove). The micro formability of 3 dimensional Patterns was also evaluated using Pyramidal type micro dies.