Due to the ever-advancing technology in various production industries, the materials of machined products have been diversified from simple steel materials to composite materials, powder metallurgy materials and silicon. Powder metallurgy materials have excellent mechanical/chemical properties, but have disadvantages such as; difficulty in processing using conventional processing methods, increased processing cost and generation of a large amount of dust. In addition, the need for the development of specialized machine tools increases due to the disadvantages such as the frequent occurrence of burrs in tapping and drilling. In order to solve the problem of machining of high hardness sintered products, a method of maximizing productivity and efficiency by processing the powder metallurgy material before it is completely sintered is being studied. In this study, structural analysis of a turret center for the verification of structural stability of a turret center for processing powder metallurgy materials was carried out. In addition, the shape was optimized to improve the structural stability and weight and presented an optimal model. The study aimed at developing more reliable turret center through the optimized model.

Recently, traffic accidents and damage on the highway have increased because of overloaded vehicles. The existing overload-detecting system has a low accuracy rate. An overload-detecting system using a weigh-in-motion (WIM) system has been developed to solve this problem. The WIM system can be used to detect overloaded vehicles by measuring the weight of the vehicles. The WIM system is divided into high-speed and low-speed types. The inaccuracy rate in the lowspeed WIM system results mainly from the low response rate of the sensor when the velocity is moving at more than 20 ㎞/h. In this study, a low-speed overload-detecting pad with a hydraulic structure using a WIM system was developed to make the system more accurate. The structural and formal analysis was carried out by using a finite element method (FEM) in order to analyze the structural stability and the extrusion velocity of the system. In addition, a static load test was performed to confirm the linearity and accuracy of the pad.

Recently, a high-precision ball screw is an essential part of high-speed machines. However, producing high-precision ball screws has been costly and time-consuming. Nowadays, a whirling machine is used to produce high-precision ball screws efficiently. Rotating multi-tips are used to turn the ball screw in the whirling machine. In this study, a structural analysis was performed by a finite-element method to develop a whirling machine. An improved model of the whirling machine was proposed by the analysis. In addition, a thermal analysis was performed to confirm the thermal stability. The results of the analysis can be applied in order to further develop the whirling machine.

Recently, the problem of the accumulation of fine sludge from the cutting oil generated during machining processes has become a major threat to the environment. The fine sludge has adverse affects on the human body and the environment, and significantly contributes to marine pollution. However, a microfiltration technique that can process the sludge still needs to be studied and developed on a global scale. Therefore, it is necessary to develop eco-friendly equipment such as an ECO vacuum filter system and eco-friendly technologies for processing cutting oil. In this study, a structural analysis was carried out using a finite element method (FEM). Improved models of the suction chamber for the ECO vacuum filter system were proposed based on the analysis of the displacement and stress of the system. The model with the best result was then optimized using the commercial software, ANSYS. It was confirmed that, in the optimized model, displacement and stress were reduced in comparison with the initial model. Finally, the structural stability of the optimized model was verified through analysis.

Laser-Assisted machining (LAM) is a new method for processing hard-to-cut materials. However, curved shapes are difficult to predict the preheating effect of by LAM because heat sources are changed by moving laser module. So, it is necessary to study the preheating effect of the laser heat source irradiated on a 3-dimensionally shaped workpiece, such as a NURBS shaped workpiece. In this study, thermal analysis and preheating experiment of the LAM for the NURBS shaped workpiece are performed. Also, two machining methods are proposed to avoid interference of laser module and cutting tool. The results of the analysis can be applied to various shaped workpieces by LAM.