• Progress in Superconductivity and Cryogenics
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• v.3 no.1
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• pp.45-49
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• 2001

A magnet supporting post installed between the lower TF coil tooled by 4.5 K supercritical helium and the cryostat base is one of the most important components of the superconducting magnet supporting structure for KSTAR Tokamak. This structure should be flexible to absorb thermal shrink of the magnet and also should be rigid to support the magnet weight and the Plasma disruptions load. The Post was designed with stainless steel 316LN and CFRP that have low thermal conductivity and high structural strength at low temperature. In order to verify the possibility of fabrication and the structural safety. a whole scale prototype of the KSTAR magnet supporting post was manufactured and tested. Static and compressive cyclic load tests under the maximum Plasma vertical disruption load and the magnet dead weight were performed. The teat results showed that the magnet supporting post of KSTAR Tokamak was possible to manufacture and structurally rigid.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.6
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• pp.838-847
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• 2004

The effect of a metal mold on densification behavior of stainless steel 316L powder was investigated under warm isostatic pressing with a metal mold. We use lead as a metal mold and obtain experimental data of metal mold properties. To simulate densification behavior of metal powder, elastoplastic constitutive equation proposed by Shima and Oyane was implemented into a finite element program (ABAQUS) under warm die pressing and warm isostatic pressing with a metal mold. Finite element results were compared with experimental data for densification and deformation of metal powder under warm isostatic pressing and warm die pressing.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1106-1116
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• 1994

Leak Before Break(LBB) design concept is applied to piping systems of newly-built Yonggwang 3, 4 nuclear generating stations as a design alternative to the provision of pipe whip restraints, in recognition of the questionable benefits of providing such restraints. The objective of this paper is to evaluate the material properties (tensile and fracture toughness) of SA312 TP316 stainless steel and their associated welds manufactured for shutdown cooling system of Yonggwang 3, 4 nuclear generating stations. Effect of various parameters such as specimen orientation, test temperature, welding on material properties were examined.

• Transactions of Materials Processing
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• v.21 no.2
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• pp.107-112
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• 2012

Gas-assisted injection molding(GAIM) produces parts with hollow internal sections. The technique offers benefits to powder injection molding(PIM), with lower material usage and reduced time for de-binding processes. In this study, the effects of processing parameters on gas penetration length of gas-assisted powder injection molding(GAPIM) were investigated for SUS316L stainless steel powder feedstock. Experiments were planned based on the Taguchi method, involving processing variables such as melt temperature, shot size, gas pressure, and gas delay time. The most significant parameters affecting gas penetration length were gas delay time and shot size, while the effects of melt temperature and gas pressure was relatively insignificant.

• Proceedings of the KWS Conference
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• 2003.11a
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• pp.45-48
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• 2003

Over the past few decades, there has been increasing research and commercial activity in invasive and non-invasive biomedical technology. One important challenge to developing these devices involves the increasing density of electrical interconnects. Resistance spot welding is limited in the density of interconnect based on either the size of welding head or the positional precision with which a weld can be made. Development of an automated laser microwelding system would permit the continued advancement of these important biomedical technologies. The objective of this work is to demonstrate the application of pseudo-pulse Nd:YAG laser technology as an alternative to resistance spot welding in performing electrical interconnection within biomedical products. To date, some experiments have been conducted by using a pseudo-pulse 1064 nm Nd:YAG laser, a successful weld of a 25 ${\mu}{\textrm}{m}$ diameter Pt/Ir wire to a 316 stainless steel shim can be made. Another application involves welding clips, which may be used for external interconnection, to electrodeposited nickel domes that make particular interconnections to specific insulated wires within a cable. These results show a great deal of promise for developing such a process.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1352-1357
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• 2003

The effect of the metal mold on densification behavior of stainless steel 316L powder was investigated under warm isostatic pressing with metal mold. We use lead as metal mold and obtain experimental data of metal mold property. To simulate densification of metal powder, the elastoplastic constitutive equation proposed by Shima and Oyane was implemented into a finite element program (ABAQUS) under warm die pressing and warm isostatic pressing with metal mold. Finite element results were compared with experimental data for densification and deformation of metal powder under warm isostatic pressing and warm die pressing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.04a
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• pp.321-327
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• 1991

High power laser beams are used in a wide variety of materials processing applications such as cutting, welding, drilling and surface treatment. The CO$\sub$2/ laser is increasingly used in laser beam welding because of the highly potential advantages. High power laser welding is a high energy density, no filler metals and low heat input process to join metals. As the comparison with the conventiona welding, precision work and good fit-up to join the metals are required and maintenance is expensive at present. The principal variables of laser beam welding are the laser beam power, travel speed and bean spot size. The penetration depth during laser beam welding is directly related to the power density of the laser beam. Generally, for a constant beam size, the penetration depth increases with increasing laser beam power.

• Journal of the Korean Society for Railway
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• v.6 no.4
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• pp.265-272
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• 2003

The computer program for the accelerated life testing technique of a machine part under the service conditions is developed under the GUI environment so that the user can easily obtain the results by selecting the program module. Also, the theoretical backgrounds for the computer program and the procedures of the accelerated testing method are introduced by testing the specimens made of the stainless steel 316L under the high temperature and random loading. The reliability of the program is discussed by the experimental results of the fatigue life, age degradation and accelerated testing conditions.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.179-179
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• 2013

Surface resistance of electro-deposited copper with its thickness, current density and surface roughness was determined by using a 4-point probe analyzer. The copper was prepared electrochemically on 316 stainless steel substrate in copper sulfate solution at the condition of $1A/dm^2$, 298 K, and 6.5 cm-electrode distance. The surface resistance of the copper sheet in the range of $0.93-0.97{\Omega}$ increased with the copper thickness in the range of $21-70{\mu}m$. The surface resistance in the range of $0.963-1.009{\Omega}$ also increased with current density in the range of $0.5-2A/dm^2$. The increased surface resistances corresponded to 11% for thickness and 25% for current density, respectively.

• Journal of Technologic Dentistry
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• v.23 no.1
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• pp.21-30
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• 2001

For biomedical applications. Ti-X%Zr-Y%Pd(X: $10{\sim}20$, Y:0.2 or 0.4) based alloys not containing harmful Al and V were newly designed, and polarization curves for their alloys were measured at $37^{\circ}C$ in 5% HCl solution in order to understand effects of Zr on the corrosion. From the results of anodic polarization behavior, it was found that the corrosion resistance increased with increasing Zr content. The results show their potential to develope Ti-based alloys for biomedical materials. The Ti-20%Zr-0.2%Pd alloy shows excellent corrosion resistance and was superior to those of the Ti. Ti-6%Al-4%V ELI alloy, Co-30%Cr-6%Mo alloy and STS 316L stainless steel.