کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1447569 988649 2010 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The effect of precipitate size on the yield strength-pitting corrosion correlation in Al–Cu–Mg alloys
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
The effect of precipitate size on the yield strength-pitting corrosion correlation in Al–Cu–Mg alloys
چکیده انگلیسی

The effect of precipitate size and state on the combinations of yield strength and corrosion pit susceptibility exhibited by a model aluminum alloy Al–2.5Cu–1.5 Mg (wt.%) has been measured for the first time. For aging times less than 2 h at 200 °C, it is shown that the fine nanoscale precipitates that form strongly affect the yield stress of the alloy but do not contribute to electrochemical heterogeneity that leads to corrosion susceptibility. This illustrates that a precipitate size range exists where the usually observed inverse correlation between strength and corrosion resistance can be broken. At longer aging times, when the precipitates become larger, a three orders of magnitude increase in the pitting rate is observed between aging times of 2 h and 9 h. The step change in pitting rate corresponds with a critical precipitate size lying between ∼3 nm and 8 nm and it is hypothesized that this size corresponds to a critical size above which it is not possible for the formation of a continuous protective passive oxide film to occur.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 58, Issue 18, October 2010, Pages 5941–5948
نویسندگان
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