NING Yuantao LI Yongnian Kunming Institute of Precious Metals
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Kunmmg
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China Professor
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Kunming Institute of Precious Metals
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Kunming
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Yunnan
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China
金属学报(英文版)
The internal oxidation behavior of Pd-40Ag-1M(M=Zr,Y)alloy wires has been studied in air at 800—1200℃.The relationship between the internal oxidation depth ξ and the reaction time t can be expressed as ξ= Kt~n,where n=0.5—0.75.The higher the temperature,the larger the value of n is.The active elements Zr and Y show different internal oxidation characters.For the alloys eontaining Zr,the oxidation rate along the grain boundaries is about twice as high as that in grains,and“lateral oxidation”exists along the grain boundaries.For the alloys containing Y,the oxidation rates in grains and along the grain boundaries are roughly the same,and there is no“lateral oxidation”along the grain bounda- ries.The activation energies of both alloys are in the range of 120—150kJ/mol.Some prop- erties for oxidized alloys were studied.The mechanisms of the internal oxidation were dis- cussed.
关键词:
Pd-40Ag alloy
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宁远涛
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李永年
金属学报
在800—1200℃大气气氛中研究了直径0.1-2.0mmPd-40Ag-1Zr和Pd-40Ag-1Y合金丝的内氧化行为及其对性能的影响、内氧化深度ξ与反应时间t的关系可以表示为ξ=Kt~n,其中反应指数n=0.5-0.75。温度越高,n值越大,对内氧化抛物线规律偏离越大,活性元素Zr和Y有不同内氧化特性:含Zr合金晶界氧化速度比晶内氧化约快一倍,且沿晶界存在“侧氧化”;含Y合金晶界与晶内氧化速度相差不大,不存在沿晶界的“侧氧化”。两种合金的内氧化激活能在120—150kJ/mol范围内。讨论了两种合金的内氧化机制。
关键词:
Pd-40Ag合金
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Y
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Zr
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internal oxidation
