• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.04a
• /
• pp.605-609
• /
• 1996

In order to ensure that the prototype corresponds as closely as possible to the serial part subsequently to be manufactured, the materials used for the prototye should, wherever possible, be identical to those used in production. In case of metallic parts, however, this demand is still not completely fulfilled by the available Rapid Prototyping techniques. Since only conventional manufacturing processes caan currentlybe used to produce metallic prototypes directly, these are extremely cost and labor intensive. For this reason, work is being undertaken worldwide to develop Selective Laser Sintering (referred to SLS) and Laser Generating for direct manufacture of metallic parts. In this paper the results of both process developments are reported. As the present results show, they have great application potentials in prototyping tools, especially molds and dies.

• Corrosion Science and Technology
• /
• v.15 no.2
• /
• pp.78-83
• /
• 2016

The e-coating to inhibit induced corrosion can deposit a coating not only on the exterior surface but also on the inside of whole metallic components of body-in-white (BIW). But it is difficult to deposit paint films on the inside area because metallic components are multi layered. It may cause shortness of e-coating thickness. The only way to properly verify e-coating thickness is by performing the use of tear-down prototypes. When paint films' thickness is inadequate, a structural modification on each metallic component is needed. Verification of the thickness improvement for a structural modification requires much manual effort and leads to increasing development time. Recently, the simulation technology has been developed to predict the e-coating thickness in e-coating field. By applying the simulation to BIW, improvement in paint thickness quality and shortening of development period are expected. The paper explains a validated solution that allows simulating the effect of design changes to the e-coating thickness and current density, thereby delivering results within a time frame of a few days.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.191-194
• /
• 1995

The business of manufacturing is increasingly becomeing time-compresssing, precise and long-life oiented, owing to various needs form the consumers and harsh global competition. with the emergence of the layer laminate maunfacturing methods, it is possible to prototypes directly from 3D CAD and additive process, the production time and cost have shortened dramatically. However there are some problems like surface-step, dimensional deviation and warp. A newly developed powder casting is suitable for rapid-manufacturing metallic tools. Powder casting can serve as a promising repid tooling method because of high density charateristics and low dimensional shrinkage below 0.1% during sintering and infiltration. By this process, we have realized significant time savings bypassing the wait for prototype tooling and cost savings eliminating the expense of conventional prototype tooling process.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.7
• /
• pp.85-90
• /
• 1998

The business of manufacturing is increasingly becoming time-compressing, precise and long-life oriented, owing to various needs from the consumers and harsh global competition. With the emergence of the layer laminate manufacturing method, it is possible to produce prototypes directly from 3D CAD and additive process, the production time and cost have shortened dramatically. However there are some problems like surface-step, dimensional deviation and warp. A newly developed powder casting is suitable for rapid-manufacturing metallic tools. Powder casting can serve as a promising rapid tooling method because of high density characteristics and low dimensional shrinkage below 0.1％ during sintering and infiltration. By this process, we have realized significant time savings bypassing the wait for prototype tooling and cost savings eliminating the expense of conventional prototype tooling process.

• The Journal of the Korea Contents Association
• /
• v.14 no.1
• /
• pp.1-13
• /
• 2014

RP(Rapid prototyping) technology is widely used to reduce the cost and cycle time of new prototypes in industries as new product development cycle time currently shortened and the voice of customers also become to be diversified. In this study, RP skill used in making jewelry products was adapted to develop the metallic inlaying base of traditional handicraft products as the significance of CAD/CAM technologies was increased. The RP technology showed that it helped the handicraftsman to cut the groove for inlaying metalic wire more easily, uniformly and diversely than conventional handicraft technique in making the groove with undercut shape. Therefore this study showed that RP technology applied for the metalic inlaying base achieved more elaborate, intricate and uniform patterns, not depending on craftsmanship, compared with conventional handicraft skill in terms of quality, cost and delivery.

• Progress in Superconductivity
• /
• v.4 no.1
• /
• pp.1-9
• /
• 2002

Transferring single flux quanta across a Josephson junction at an exactly determined rate has made highly precise voltage measurements possible. Making use of self-shunted Nb-based SINIS junctions, programmable fast-switching DC voltage standards with output voltages of up to 10 V were produced. This development is now extended from fundamental DC measurements to the precise determination of AC voltages with arbitrary waveforms. Integrated RSFQ circuits will help to replace expensive semiconductor devices for frequency control and signal coding. Easy-to-handle AC and inexpensive quantum voltmeters of fundamental accuracy would be of interest to industry. In analogy to the development in the flux regime, metallic nanocircuits comprising small-area tunnel junctions and providing the coherent transport of single electrons might play an important role in quantum current metrology. By precise counting of single charges these circuits allow prototypes of quantum standards for electric current and capacitance to be realised. Replacing single electron devices by single Cooper pair circuits, the charge transfer rates and thus the quantum currents could be significantly increased. Recently, the principles of the gate-controlled transfer of individual Cooper pairs in superconducting A1 devices in different electromagnetic environments were demonstrated. The characteristics of these quantum coherent circuits can be improved by replacing the small aluminum tunnel Junctions by niobium junctions. Due to the higher value of the superconducting energy gap ($\Delta_{Nb}$ ＝ $7\Delta_{Al}$), the characteristic energy and the frequency scales for Nb devices are substantially extended as compared to A1 devices. Although the fabrication of small Nb junctions presents a real challenge, the Nb-based metrological devices will be faster and more accurate in operation. Moreover, the Nb-based Cooper pair electrometer could be coupled to an Nb single Cooper pair qubit which can be beneficial for both, the stability of the qubit and its readout with a large signal-to-noise ratio..