• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 추계학술대회 논문집
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• pp.21-24
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• 2000

Ultra-fine grains were produced in pure Al using an Accumulative Rolling-Bonding (ARB) process. After several cycles of the ARB process, pure Al sheets were filled with the ultra-fine grains whose diameters were several hundred nano-meters. With ARB cycles, the nature of grain boundaries of the ultra-fine grains changed from diffusive sub-boundaries to well-defined high angle boundaries. After 7 cycles, ultra-fine polycrystals with large misorientations between neighboring grains were obtained. Sliding wear tests using a pin-on-disk type wear tester were co ducted on the ultra-fine grained pure Al. Wear rates of pure Al increased with the increase of ARB cycle numbers in spite of the increase in hardness. Worn surfaces and cross-sections were examined with optical microscopy (OM) and scanning electron microscopy (SEM) In investigate the wear mechanism of the ultra-fine grained pure Al.

• 대한금속재료학회지
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• 제49권11호
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• pp.893-899
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• 2011

Fabrication of a complex aluminum alloy by the ARB process using dissimilar aluminum alloys has been carried out. Two-layer stack ARB was performed for up to six cycles at ambient temperature without a lubricant according to the conventional procedure. Dissimilar aluminum sheets of AA1050 and AA5052 with thickness of 1 mm were degreased and wire-brushed for the ARB process. The sheets were then stacked together and rolled to 50% reduction such that the thickness became 1 mm again. The sheet was then cut into two pieces of identical length and the same procedure was repeated for up to six cycles. A sound complex aluminum alloy sheet was successfully fabricated by the ARB process. The tensile strength increased as the number of ARB cycles was increased, reaching 298 MPa after 5 cycles, which is about 2.2 times that of the initial material. The average grain size was $24{\mu}m$ after 1 cycle, and became $1.8{\mu}m$ after 6 cycles.

• 한국중재학회지:중재연구
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• 제30권4호
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• pp.51-70
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• 2020

The Mediation-Arbitration hybrid is becoming more popular since it makes an amicable relationship and thorough statement possible. The Mediation-Arbitration hybrid has been used to take advantage of both dispute resolution methods. In a Med-Arb process, negotiating a resolution to disputes is attempted with a mediator's help. If the mediation ends in an impasse or issues remain unresolved, parties can move on to arbitration. Med-Arb can also be cost-effective when disputants hire one person to serve as mediator and arbitrator (Med-Arb-Pure). However, it can disturb the fairness and neutrality of arbitrators, and awards can be annulled. Indeed, "Award by Consent" is different from the "Med-Arb-Pure" process. Arbitrators easily confuse them. Only the parties settle on the arbitral proceedings' course, and the arbitrator can help them (award by consent). The role and skill of a mediator are different from an arbitrator's. Disputants have the right to use a mediator who specializes in mediation. Moreover, mediation communication confidentiality is the essential value of mediation, and this should be protected. Therefore, in the process of "Med-Arb," separation between mediating and arbitrating is a better choice to specialize in each expertise. In this process, "Med-Arb" can be an affordable, expeditious, proper, and effective method of resolving international commercial disputes and continuing ADR prime time.

• 한국재료학회지
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• 제17권10호
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• pp.521-525
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• 2007

The microstructure and mechanical properties of an oxygen free copper processed by accumulative roll bonding(ARB) at low strain rate were studied. The copper sheets were highly strained up to an equivalent strain of ${\sim}6.4$ by ARB process at ambient temperature. The strain rate of the copper during the ARB was $2.6sec^{-1}$. The microstructure and mechanical properties of the ARB-processed copper were compared to those of the specimens processed by ARB at relatively high strain rate ($37sec^{-1}$). The microstructure and mechanical properties of the copper with ARB process was very similar to each other despite of some differences in recovery.

• 한국중재학회지:중재연구
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• 제24권1호
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• pp.85-109
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• 2014

Mediation and Arbitration are two distinct ADR processes. Their dissimilarity lies in the principle that in mediation the parties themselves decide what the resolution to the problem is, whereas in arbitration the arbitrator makes that determination. Med-Arb, hybrid of the two methods, is a fairly new ADR process dating back to the 1970s. Med-Arb capitalizes on the advantages of both mediation and arbitration, while eliminating many of their disadvantages. Mediation has the advantage of allowing for resolutions rather than decisions. Arbitration has the advantage of guaranteeing that the matter will be resolved when the procedure is over. In Med-Arb, the participants agree to be parties to mediation, and if the mediation comes to an impasse, a final settlement will be reached through arbitration. This study first explicates the origin and the development of Med-Arb in the United States. This study shows that the emergence of Med-Arb is benefited from the fact that arbitration has lost its own advantages ie, speed, cost-saving, and maintenance of an ongoing relationship between the disputants. Second, this study analyzes four cases in which Med-Arb is applied to various kinds of disputes as a tool of dispute resolution: labor disputes, entertainment disputes, will disputes, and international commercial disputes, consecutively. All those case studies show the generality of Med-Arb as a dispute resolution channel. Third, this study compares the advantages and disadvantages of Med-Arb. Finally, this study discusses the implications of Med-Arb. In particular it provides the universality of this hybrid form of dispute resolution in the East and West. For example, we show that China has its own distinctive Med-Arb system, where it has developed from ancient Confucian philosophy. Japan also emphasizes the role of an arbitrator who settles the disputes in the course of arbitration. The domestic arbitration rules of the Korean Commercial Arbitration Board (KCAB) have a similar process in that arbitration contains an element of conciliation. With regard to the universal characteristics of Med-Arb, it is necessary to analyze the pros and cons of Med-Arb at a deeper level in the future. One caveat is that it is necessary to handle the issues of the neutrality of the mediator-arbitrator.

• 한국분말재료학회지
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• 제13권1호
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• pp.39-45
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• 2006

The $Al/SiC_p$ particle reinforced composite fabricated by a powder-in sheath rolling (PSR) method was severely. deformed by the accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubricant. The ARBed composite exhibited an ulbricant. grained structure similar to the other ARBed bulky materials. Tensile strength of the composite increased gradually with the number of ARB cycles, but from the 6th cycle it rather decreased slightly. These characteristics of the composite were somewhat different from those of Al powder compact fabricated by the same procedures. The difference in microstructure and mechanical properties between Al powder compact and the composite was discussed.

• 한국분말재료학회지
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• 제12권1호
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• pp.30-35
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• 2005

An aluminum powder compact consolidated by a powder-in sheath rolling (PSR) method was severely deformed by accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubrication. Optical microscope and transmission electron microscope observations revealed that microstructure of the ARB-processed Al powder compact is inhomogeneous in the thickness direction. The ultra-fine subgrains often reported in the ARB-processed bulky materials were also developed near surface of the Al powder compacts in this study. Tensile strength of the ARB-processed Al powder compact increased at the 1st cycle, but from the 2nd cycle it rather decreased slightly.

• 소성∙가공
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• 제14권1호
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• pp.71-77
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• 2005

Thermal stability and dry sliding wear behavior of ultra-fine grained 6061 Al alloy fabricated by an accumulative roll-bonding (ARB) process have been investigated. After 4 ARB cycles, an ultra-fine grained microstructure of the 6061 Al alloy composed of grains with average size of 500nm, and separated mostly by high-angle boundaries was obtained. Though hardness and tensile strength of the ARB processed Al alloy increased with ARB cycles up to 4 cycles, the processed alloy exhibited decreased ductility and little strain hardening. Thermal stability of the ARB-processed microstructure was studied by annealing of the severely deformed alloy at $423K{\sim}573K$. The refined microstructure of the alloy remained stable up to 473K, and the peak aging treatment of the alloy at 450K for 8 hrs increased the thermal stability of the alloy. Sliding-wear rates of the alloy increased with the number of ARB cycles in spite of the increased hardness with the cycles. Wear mechanisms of the ultra-fine grained alloy were investigated by examining worn surfaces, wear debris, and cross-sections by a scanning electron microscopy (SEM).

• 한국재료학회지
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• 제23권1호
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• pp.41-46
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• 2013

The microstructural evolution of AA1050/AA6061 complex aluminum alloy, which is fabricated using an accumulative roll-bonding (ARB) process, with the proceeding of ARB, was investigated by electron back scatter diffraction (EBSD) analysis. The specimen after one cycle exhibited a deformed structure in which the grains were elongated to the rolling direction for all regions in the thickness direction. With the proceeding of the ARB, the grain became finer; the average grain size of the as received material was $45{\mu}m$; however, it became $6.3{\mu}m$ after one cycle, $1.5{\mu}m$ after three cycles, and $0.95{\mu}m$ after five cycles. The deviation of the grain size distribution of the ARB processed specimens decreased with increasing number of ARB cycles. The volume fraction of the high angle grain boundary also increased with the number of ARB cycles; it was 43.7% after one cycle, 62.7% after three cycles, and 65.6% after five cycles. On the other hand, the texture development was different depending on the regions and the materials. A shear texture component {001}<110> mainly developed in the surface region, while the rolling texture components {011}<211> and {112}<111> developed in the other regions. The difference of the texture between AA1050 and AA6061 was most obvious in the surface region; {001}<110> component mainly developed in AA1050 and {111}<110> component in AA6061.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1527-1528
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• 2011