• 대한치과보철학회지
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• 제27권1호
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• pp.143-179
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• 1989

To observe the bonding behavior of palladium-based alloys to porcelain; 1. Pd-Co binary alloy with the higher cobalt content, 2. Pd-Co binary alloy with the lower cobalt content, 3. Pd-Ag-Sn ternary alloy, 4. Pd-Ag binary alloy, 5. Pd-Cu-Au ternary alloy and 6. Pd-Cu binary alloy were made as 6 groups of experimental alloys. Each group of alloy was divided into 4 sub-groups such as one sub-group that was not degassed and three sub-groups that degassed for 5 minutes, 10 minutes and 15 minutes. On each specimen, weight changes after degassing, morphological changes of oxide layer by changing the degassing time, compositional changes at metal-ceramic interface and bond strength of metal-ceramic measured with planar shear test were observed and compared. The results of the present study allow the following conclusions to be drawn: 1. The alloy showing the greatest bond strength was Pd-Cu alloy without gold and bond strength was decreased by alloying gold to them. 2. Although Pd-Co alloy showed the most prominent oxidation behavior, bond strength of them to porcelain was not greatly high by the formation of porosities at metal-ceramic interfaces. 3. Likewise tin, cobalt formed the peaks on line profiles at metal-ceramic interface, however copper did not exhibit such peaks on line profiles. 4. Mainly, oxide layer on Pd-Co alloy was composed with cobalt, and for Pd-Co alloy with higher cobalt content the rise of bond strength was not significant by increased degassing time. 5. On Pd-Ag alloy not containing tin, during degassing for 15 minutes silver content was increased at metal-ceramic interface. 6. As an oxidized element, tin formed the oxide layers that widen their area by increasing the degassing time, while cobalt and copper showed the morphological changes of particle or crystal on oxide layer.

• 구강회복응용과학지
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• 제22권2호
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• pp.125-136
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• 2006

Statement of problem. The success of the bonding between electroforming gold and resin is dependent on the surface-conditioning technique but its effective technique has net been studied widely. Purpose. The purpose of the study was to evaluate the bond strength between the electroforming gold and resin with varying the surface-conditioning technique. Materials and methods. Sixty rectangular shaped metal specimens were made and one side of each specimen were gold hard plated. The sand-blasted specimens were divided into four experimental groups with fifteen specimens in each group and were treated as follows. Group 1: Silicoating (Rocatec, 3M ESPE)+ Sinfony (3M ESPE), Group 2: SR Link+ SR Adoro (Ivoclar Vivadent), Group 3: Tin plating (Microtin, Danville Engineering)+ SR Link+ SR Adoro, Group 4: Tin plating (Micro tin, Danville Engineering)+ Silicoating (Rocatec)+ Sinfony. Shear bond strength at metal-resin interface were measured using universal testing machine. Energy Dispersive x-ray analysis was done and scanning electron microscope images were taken and observed. Results and Conclusion. The following conclusions were drawn. 1. The mean shear bond strength values in order were 11.69MPa (Group 2), 22.35MPa (Group 3), 22.40MPa (Group 1) and 27.71MPa (Group 4). There was no significant difference in Group 1, Group 3 and Group 4(P>0.05). 2. In the EDX line analysis, the Au was detected on the surface of all specimen. $SnO_2$ showed on the surface of Group 2 and $SiO_2$ was detected on the surface of Group 1. 3. Increasing of roughness by sandblasting(Group 2), formation of micro-irregularities and tin crystals by electrolytic tin plating(Group 3) and formation of surface irregularities and $SiO_2$ layer(Group 1,4) were observed in SEM photo. 4. Tin plating(Group 3) and Rocatec treatment(Group 1) showed clinically effective shear bond strength(>20MPa), but when the two surface conditioning method were used together higher bond strength were achieved.

• 보존과학회지
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• 제28권2호
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• pp.175-184
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• 2012

본 연구는 몽골 도르릭나르스 유적 2호, 3호 및 4호분에서 출토된 청동제 및 금제 유물에 대한 과학적 분석 결과로부터 각 유적 출토품의 특징을 알아보는데 그 목적이 있다. 몽골의 흉노무덤인 도르릭나르스 유적 2호, 3호 및 4호분은 비교적 소형이고, 도굴 된 상태였음에도 불구하고 많은 유물이 다양하게 출토되었다. 특히 출토 유물에는 중국계 유물과 북방계 유물이 공존하고 있어 매우 중요한 유적으로 평가되고 있다. 먼저 청동 용기류의 경우 중국제인 한경이나 일산살 꼭지의 성분 조성과는 달리 주석에 비하여 납의 함유량이 높은 특징을 보였는데, 특히 2호의 청동쟁반, 청동등잔 그리고 4호의 청동솥의 경우는 주석이 1wt% 정도로 적게 함유되어 있어 Cu-Pb의 2원계 합금 조성을 보였다. 금제품의 경우는 2호분 장식품의 제작에 비교적 높은 순도의 금이 사용된 것으로 조사되었으며, 금제 누금 장식의 금 알갱이의 접합에는 금과 구리를 합금한 금땜이 사용되었거나 확산접합(말라카이트나 산화구리 화합물 가루를 사용함)에 의하여 접합했을 가능성이 높았다. 향후 몽골지역 뿐만 아니라 다른 지역의 흉노 무덤 출토품에 대한 과학적 조사 및 분석이 더 많이 진행된다면 흉노 문화에 대한 더 많은 문제들을 해결할 수 있는 실마리를 제공하게 될 것이다.