کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1657968 1517657 2013 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of electrical parameters on plasma electrolytic oxidation of aluminium
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Effects of electrical parameters on plasma electrolytic oxidation of aluminium
چکیده انگلیسی

The plasma electrolytic oxidation (PEO) of aluminium alloys is investigated for different electrical working conditions using a pulsed bipolar current supply. A particular attention is paid to the effect of the anodic current density (from 10 to 90 A dm− 2) and current pulse frequency (from 100 to 900 Hz) on the resulting oxide layer. Micro-discharges are characterized during the process by means of fast video imaging with a time and a space resolution of 8 μs and 0.017 mm2, respectively. Correlations are established between the micro-discharge characteristics (surface density, lifetime and size) and the elaborated oxide layers (morphology, growth rate and surface roughness). The highest coating growth rate measured (2.1 μm min− 1) is achieved with the combination of the highest current density (75.7 A dm− 2) and the highest current pulse frequency (900 Hz). Within these specific current conditions it is concluded that the detrimental effects of numerous micro-discharges are minimized. The results also show that the surface roughness may be largely affected by the presence of long-lived and large micro-discharges which develop over the processed surface. The strongest micro-discharges (live duration up to 0.3 ms and cross-sectional area up to 1 mm2) are mainly observed with the combination of the highest current density (75.7 A dm− 2) and the lowest current pulse frequency (100 Hz).


► Effects of anodic current density and pulse frequency in PEO process are investigated.
► Fast-video (8 μs/0.017 mm2 resol.) is used to characterize micro-discharges (MDs).
► Characteristics of MD and some properties of PEO coatings are discussed.
► Growth kinetic and roughness are correlated with strength of MDs (lifetime/size).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface and Coatings Technology - Volume 221, 25 April 2013, Pages 70–76
نویسندگان
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