Process and die design of cold forging for the asymmetric part, engine mount adapter has been studied. Forging of the asymmetric part frequently causes die failure because of the high forging load and local stress concentration of the die. Thus, performing process design of cold forging to minimize forging load is required. Preform for the engine mount adapter was chosen based on the forging load and filling rate of forgings by the finite element analysis. In the die design, number of stress rings, interface radius, and relative interference were investigated in several cases with maximum principle stress by the finite element method. The shape of the die was determined by comparing the load changing the radius of the flange area. Also, the life of the designed die was calculated using the Goodman theory by cyclic fatigue loading. As a result, it was confirmed that the calculation life and results of the test were identical. In this study, it is verified that stress concentration and fatigue life should be considered simultaneously in the design of cold forging die for the asymmetric part.

Multi-material Additive Manufacturing (AM) is being focused to apply for direct manufacturing of a product. In this paper, a three-dimensional circuit device (3DCD) fabrication technology based on the multi-material AM technology was proposed. In contrast with conventional two-dimensional Printed Circuit Board (PCB), circuit elements and conducting wires of 3DCD are placed in threedimensional configuration at multiple layers of the structure. Therefore, 3DCD technology can improve design freedom of an electronic product. In this paper, 3DCD technology is proposed based on AM technology. Two types of 3DCD fabrication systems were developed based on the Stereolithography and the Fused Deposition Modeling technologies. And the 3DCD samples which have same function were fabricated, successfully.

A internal lobe pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. In particular, the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobe with elliptical and involute shapes, while the inner rotor profile is determined as conjugate to the other. And the integrated system which is composed of three main modules has been developed through AutoLISP under AutoCAD circumstance. It generates new lobe profile and calculates automatically the flow rate and flow rate irregularity according to the lobe profile generated. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field.