• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Journal of Prosthetic Dentistry >Potentiodynamic polarization study of the in vitro corrosion behavior of 3 high-palladium alloys and a gold-palladium alloy in 5 media.
【24h】

Potentiodynamic polarization study of the in vitro corrosion behavior of 3 high-palladium alloys and a gold-palladium alloy in 5 media.

机译：电位动力学极化法研究了5种介质中3种高钯合金和金钯合金的体外腐蚀行为。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

STATEMENT OF PROBLEM: Corrosion of cast alloy restorations may lead to their failure or adversely affect their biocompatibility. Although some documentation of the corrosion behavior of the high-palladium dental alloys exists, questions remain about their corrosion resistance and mechanisms. PURPOSE: This study compared the in vitro corrosion characteristics of 3 high-palladium alloys and 1 gold-palladium alloy in simulated body fluid and oral environments. MATERIAL AND METHODS: Two Pd-Cu-Ga alloys and 1 Pd-Ga alloy were selected; an Au-Pd alloy served as the control. The corrosion behavior for the as-cast and simulated porcelain-firing (heat-treated) conditions of each alloy (N = 5) was evaluated in 0.9% NaCl, 0.09% NaCl, and Fusayama solutions. Heat-treated specimens of each alloy (N = 5) were also tested in N(2)-deaerated 0.09% NaCl and Fusayama solutions (pH 4). After immersion in the electrolyte for 24 hours, the open-circuit potential (OCP) was measured, and linear polarization was performed from -20 mV to +20 mV (vs. OCP) at a scanning rate of 0.125 mV/s. Cyclic polarization was performed from -300 mV to +1000 mV and back to -300 mV (vs. OCP) at a scanning rate of 1 mV/s. Data were evaluated with analysis of variance and the Ryan-Einot-Gabriel-Welsch multiple-range test (alpha=.05). RESULTS: The OCP of each alloy varied with the condition (as-cast or heat-treated) and electrolyte used. Corrosion resistance was similar for the 4 alloys tested. For cyclic polarization, all alloys showed active-passive or spontaneous passive behavior in nearly all electrolytes. During some reverse scans, the 3 high-palladium alloys displayed 3 or 5 anodic peaks. No positive hysteresis was observed for any of the alloy/electrolyte combinations evaluated. CONCLUSION: The corrosion resistances of the 3 high-palladium alloys in simulated body fluid and oral environments were comparable to that of the gold-palladium alloy. The similar corrosion resistance for the 3 high-palladium alloys was attributed to their high noble metal content and theorized stable structure at the submicron level. Selective corrosion of different phases and elements, surface enrichment of palladium, and adsorption of species are possible corrosion mechanisms. The cyclic polarization results suggest that none of the 4 alloys would be prone to pitting or crevice corrosion under in vivo conditions, but crevice conditions should nonetheless be avoided for these alloys in the oral environment.
机译：问题陈述：铸造合金修复体的腐蚀可能导致其失效或对其生物相容性产生不利影响。尽管存在有关高钯牙科合金腐蚀行为的一些文献，但有关其耐腐蚀性和机理的问题仍然存在。目的：本研究比较了三种高钯合金和一种金钯合金在模拟体液和口腔环境中的体外腐蚀特性。材料与方法：选择两种Pd-Cu-Ga合金和1种Pd-Ga合金。以Au-Pd合金为对照。在0.9％NaCl，0.09％NaCl和Fusayama溶液中评估了每种合金（N = 5）的铸态和模拟瓷烧（热处理）条件下的腐蚀行为。还在N（2）脱气的0.09％NaCl和Fusayama溶液（pH 4）中测试了每种合金（N = 5）的热处理样品。浸入电解液中24小时后，测量开路电势（OCP），并以0.125 mV / s的扫描速率在-20 mV至+20 mV（相对于OCP）之间进行线性极化。循环极化的扫描速率为-300 mV至+1000 mV，然后回升至-300 mV（vs。OCP）。通过方差分析和Ryan-Einot-Gabriel-Welsch多范围检验（alpha = .05）对数据进行评估。结果：每种合金的OCP随使用的条件（铸造或热处理）和电解液而变化。所测试的4种合金的耐腐蚀性相似。对于循环极化，几乎所有电解质中所有合金均表现出主动-被动或自发的被动行为。在一些反向扫描中，这3种高钯合金显示3个或5个阳极峰。对于所评估的任何合金/电解质组合，均未观察到正磁滞现象。结论：3种高钯合金在模拟体液和口腔环境中的耐蚀性与金钯合金相当。 3种高钯合金的相似耐蚀性归因于它们的高贵金属含量和亚微米水平的理论上稳定的结构。不同相和元素的选择性腐蚀，钯的表面富集和物质的吸附是可能的腐蚀机理。循环极化结果表明，四种合金在体内条件下均不容易出现点蚀或缝隙腐蚀，但是对于口腔环境中的这些合金，仍应避免缝隙条件。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号