• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.12
• /
• pp.1647-1653
• /
• 2011

The cycle time in injection moulding greatly depends on the cooling time of the plastic part that is controlled by cooling channels. Cooling channels are required to facilitate the heat transfer rate from the die to the coolant without reducing the strength of the die. Employing layered manufacturing techniques (LMT), a die embedding conformal cooling channels can be fabricated directly while conventional cooling channels are usually made of straight drilled hole. Meanwhile, H13 tool steel is widely used as the die material because of its high thermal resistance and dimensional stability. However, H13 with a low thermal conductivity is not efficient for certain part geometries. In this context, the use of functionally graded materials (FGMs) between H13 and copper may circumvent a tradeoff between the strength and the heat transfer rate. This paper presents a method for modeling of conformal cooling channels made of FGMs.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.101-104
• /
• 1997

The purpose of this study is the development of the extensive Rapid Prototyping Technique, which can resolve the long-term manufacturing process, shrinkage and deformation occurring rapid prototyping technique. To begin with, the various specimens for tensile and bending test were manufactured on the basis of this modeling technology. Then, many kinds of the laminate pieces for the test were made by using the sheet steels 1 mm and 2 mm thickness which is composed of the same ingredient. Not only the mechanical strength of the both of the laminate specimens by the developed Rapid Prototyping using projection welding and non-laminate specimens of 5 mm thickness were evaluated, but the mechanical strength of the specimens of the tensile and bending test composed of heterogeneous components were also estimated.

• The Journal of the Korea Contents Association
• /
• v.15 no.1
• /
• pp.308-315
• /
• 2015

The purpose of this study, using 3D printer, was tried to fabricate the short arm cast of mesh types that can be hygienic and adequate ventilation with a good radiography. We used the multi channel computed tomography (MDCT) with three dimension printer device of the fused deposition modeling (FDM) techniques. The material is used a degradable plastic (poly lactic acid, PLA). Three-dimensional images of the short arm were obtained in the MDCT and then make the three-dimensional volume rendering. Three dimension volume rendering of the short arm is implemented as a tomography obtained in MDCT. Virtual mesh type cast model was output as three-dimensional images is designed based on the three-dimensional images of the short arm. As a results, the cast output by 3D printers were able to obtain excellent radiograph images than the conventional cast, and then it can decreased itching with unsanitary, and can break down easily to the cast. In conclusion, the proposed virtual mesh type cast output by 3D printers could be used as a basis for future three-dimensional printing cast productions and offered help to patients in the real life.