|
KMID : 0362220110380010043
|
|
Journal of The Korean Research Society for Dental Materials
2011 Volume.38 No. 1 p.43 ~ p.50
|
|
|
Effect of Compositional Difference by Presence or Absence of Beryllium on Castabilty of Dental Ni-Cr Alloys
|
|
Choi Beom-Wung
Lim Ho-Nam
|
|
|
Abstract
|
|
|
|
The purpose of this study was to confirm the compositional differences of some dental Ni-Cr alloys including beryllium component or not, by quantitative analysis and to confirm that the compositional differences had an effect on melting point and castability using castability test and differential scanning calorimetry. Total five Ni-Cr alloys were used in this study. Quantitative analysis was carried out using EPMA (electron probe micro analyzer, JEOL Company, Japan), and melting points were measured using DSC (differential scanning calorimetry, NETZSCH, German) With forementioned methods, we confirmed the effects of beryllium on melting points. For castability evaluation, the polyester mesh patterns were invested in phosphate bonded investment. Each specimen provided a grid with 100 open regular squares. The castability of each alloy was evaluated by summing up the number of those regular squares reappeared perfectly without breaking. Following results were obtained: 1. The experimental groups that containing beryllium exhibited the lower melting temperatures and the better castability than the experimental groups that beryllium was not included (p<0.05 ). 2. The component changes of molybdenum (Mo), aluminium (Al), etc in the experimental groups that contained beryllium did not have any effects on melting temperatures and castability (p>0.05 ). 3. The difference in micro-elements in the experimental groups, of which beryllium were not included, did not have any effects on melting temperatures and castability (p>0.05 ). Silicone, manganese, niobium, etc used as substitution elements of the beryllium used for improvement of castability of Ni-Cr alloys were used. But, alloys that contained these elements did not have good castability than the alloys that containing beryllium component. Therefore, the development of alloys that have biocompatibility and improved castability is necessary.
|
|
|
KEYWORD
|
|
|
2 Beryllium, Castability, Melting range, Mesh pattern, Ni-Cr alloy
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|