Surface segregation in Ni(W) solid solution

被引：14

作者：

Sagie, E ^{[1
]}

Polak, M ^{[1
]}

机构：

[1] Ben Gurion Univ Negev, Dept Mat Engn, IL-84105 Beer Sheva, Israel

来源：

SURFACE SCIENCE | 2000年 / 459卷 / 1-2期

关键词：

alloys; Auger electron spectroscopy; chemisorption; equilibrium thermodynamics and statistical mechanics; metallic surfaces; nickel; surface segregation; tungsten;

D O I：

10.1016/S0039-6028(00)00485-4

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The surface composition of Ni-7%W solid solution equilibrated under UHV in the range 750-1100 K was determined by means of quantitative Auger electron spectroscopy. Only part of the excess tungsten accumulated at the sputter-cleaned surface dissolved upon subsequent annealing, and from the temperature dependence of the residual W equilibrium concentration, quantified for two different in-depth distribution models, segregation enthalpies and excess entropies are derived. The observed tungsten surface segregation tendency indicates dominance of elastic strain release over weakened interatomic bonding driving forces in this solid solution. Tungsten segregation levels are relatively low because of the small net energetic driving force, and due to a suppressing excess entropy effect. Adsorption of oxygen on the alloy surfaces enhances W segregation at elevated temperatures due to preferential W-O interactions. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：223 / 229

页数：7

共 23 条

[1] SURFACE SEGREGATION IN BINARY SOLID-SOLUTIONS - A THEORETICAL AND EXPERIMENTAL PERSPECTIVE [J].

ABRAHAM, FF ;

BRUNDLE, CR .

JOURNAL OF VACUUM SCIENCE & TECHNOLOGY, 1981, 18 (02) :506-519

[2]

[Anonymous], INTERFACIAL SEGREGAT

[3]

BARTELLA J, 1983, P 9 IVC V ICSS MADR

[4]

BETZ G, 1983, SPUTTERING PARTICLE, V2

[5] TRENDS IN COHESIVE ENERGY OF TRANSITION-METAL ALLOYS [J].

COLINET, C ;

PASTUREL, A ;

HICTER, P .

CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY, 1985, 9 (01) :71-99

[6]

Dowben P.A., 1990, SURFACE SEGREGATION

[7] PREFERENTIAL SPUTTERING AND RADIATION ENHANCED SEGREGATION IN PALLADIUM PLATINUM ALLOYS [J].

DUPLESSIS, J ;

VANWYK, GN ;

TAGLAUER, E .

SURFACE SCIENCE, 1989, 220 (2-3) :381-390

[8] SEGREGATION OF TIN ON (111) AND (100) SURFACES OF COPPER [J].

ERLEWEIN, J ;

HOFMANN, S .

SURFACE SCIENCE, 1977, 68 (01) :71-78

[9] Preferential sputtering and surface segregation of CuZr alloys [J].

Kang, HJ ;

Kim, CH ;

Park, NS ;

OConnor, DJ ;

MacDonald, R .

APPLIED SURFACE SCIENCE, 1996, 100 :329-332

[10] SURFACE SEGREGATION IN PTRH ALLOYS REVISITED IN THE FRAMEWORK OF THE TIGHT-BINDING ISING-MODEL [J].

LEGRAND, B ;

TREGLIA, G .

SURFACE SCIENCE, 1990, 236 (03) :398-408

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