The role of macrostructural and microstructural morphologies on the corrosion resistance of Zn and a Zn-4% Al alloy

被引：17
作者：
Osorio, W. R. [1 ]
Spinelli, J. E. [1 ]
Freire, C. M. [1 ]
Garcia, A. [1 ]
机构：
[1] Univ Estadual Campinas, Dept Mat Engn, BR-13083970 Campinas, SP, Brazil
来源：
MATERIALS AND MANUFACTURING PROCESSES | 2007年 / 22卷 / 03期
基金：
巴西圣保罗研究基金会;
关键词：
chill mold; columnar grains; corrosion resistance; corrosion tests; electrochemical impedance spectroscopy ( EIS); equiaxed grains; grain size; macromorphology; micromorphology; polarization tests; secondary dendrite arm spacing; unidirectional solidification; water-cooled mold; zinc; Zn-Al alloys;
D O I：
10.1080/10426910701190386
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
Different structural morphologies may develop due to a wide range of the operational conditions that may exist during casting. It is well known that corrosion resistance and mechanical properties depend on solidi. cation structures. The aim of this study is to investigate both the influence of columnar and equiaxed structures of zinc as-cast samples and of dendritic microstructural array of a Zn-Al alloy on the corrosion resistance. In order to obtain columnar and equiaxed structures, both a vertical upward solidi. cation apparatus and a permanent steel mold casting assembly were used. The corrosion resistance was analyzed using electrochemical impedance spectroscopy and Tafel extrapolation. Corrosion tests were conducted in a 3% (vol.) NaCl solution at room temperature. It was found that coarser macrostructures tend to provide higher corrosion resistance for both columnar and equiaxed morphologies. On the other hand, finer secondary dendrite arm spacing is conducive to a better corrosion behavior of a Zn-4% Al alloy.
引用
收藏
页码：341 / 345
页数：5
相关论文
共 14 条
[1]   Modelling microstructural and mechanical properties of ferritic ductile cast iron [J].
Donelan, P .
MATERIALS SCIENCE AND TECHNOLOGY, 2000, 16 (03) :261-269
[2]  
Flemings M., 1974, The solidification processing
[3]   Secondary dendrite arm spacing and solute redistribution effects on the corrosion resistance of Al-10 wt% Sn and Al-20 wt% Zn alloys [J].
Osório, WR ;
Spinelli, JE ;
Cheung, N ;
Garcia, A .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2006, 420 (1-2) :179-186
[4]   Dendritic solidification microstructure affecting mechanical and corrosion properties of a Zn4Al alloy [J].
Osório, WR ;
Freire, CMA ;
Garcia, A .
JOURNAL OF MATERIALS SCIENCE, 2005, 40 (17) :4493-4499
[5]   The role of macrostructural morphology and grain size on the corrosion resistance of Zn and Al castings [J].
Osório, WR ;
Freire, CM ;
Garcia, A .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2005, 402 (1-2) :22-32
[6]   The effect of the dendritic microstructure on the corrosion resistance of Zn-Al alloys [J].
Osório, WR ;
Freire, CM ;
Garcia, A .
JOURNAL OF ALLOYS AND COMPOUNDS, 2005, 397 (1-2) :179-191
[7]   Mechanical properties as a function of thermal parameters and microstructure of Zn-Al castings [J].
Osório, WR ;
Santos, CA ;
Quaresma, JMV ;
Garcia, A .
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, 2003, 143 :703-709
[8]   Modeling dendritic structure and mechanical properties of Zn-Al alloys as a function of solidification conditions [J].
Osório, WR ;
Garcia, A .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2002, 325 (1-2) :103-111
[9]  
PETCH NJ, 1953, J IRON STEEL I, V174, P25
[10]   Determination of transient interfacial heat transfer coefficients in chill mold castings [J].
Santos, CA ;
Quaresma, JMV ;
Garcia, A .
JOURNAL OF ALLOYS AND COMPOUNDS, 2001, 319 (1-2) :174-186
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