رفتار خوردگی پوشش‌های نانوبلورین نیکل اعمالی بر روی آلیاژ منیزیم AZ91 به‌روش آب‌کاری الکتریکی

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه تهران

2 دانشگاه علم و صنعت ایران

3 دانشگاه آزاد یزد

چکیده

در این تحقیق، پوشش نیکل به‌روش آب‌کاری الکتریکی بر روی آلیاژ منیزیم AZ91 اعمال شد و مقاومت به‌خوردگی آن با آلیاژ منیزیم AZ91 و نیکل خالص با استفاده از آزمون‌های پلاریزاسیون و طیف‌سنجی امپدانس الکتروشیمیایی (EIS) در محلول 5/3 درصد وزنی کلرید سدیم مقایسه شد. ساختار پوشش با آزمون پراش پرتوی ایکس (XRD) ومُرفولوژی و ترکیب شیمیایی آن با استفاده از میکروسکُپ الکترونی روبشی (SEM) بررسی شد. بررسی‌ها نشان دادند که پوشش دارای ساختار نانوبلورین با میانگین اندازه دانه‌ی 95 نانومتر می باشد. نتایج آزمون خوردگی نشان دادند که چگالی جریان خوردگی ازA/cm2 4-10×5/2 برای نمونه‌ی بدون پوشش تا A/cm2 5-10×5/1 کاهش می‌یابد و پتانسیل خوردگی افزایش می‌یابد.

کلیدواژه‌ها


عنوان مقاله [English]

Corrosion Behavior of Electrodeposited Nickel Coatings on AZ91 Mg Alloy

نویسندگان [English]

  • Arman Zarebidaki 1
  • Mohammad-Reza Aboutalebi 2
  • hassan mahmoudikohani 3
1 Department of Metallurgical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran.
2 School of Metallurgy and Materials Engineering, Iran University of Science and Technology, 16846-13114, Tehran, Iran.
3 Department of Metallurgical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran.
چکیده [English]

In this study, nickel was electrodeposited onto the surface of AZ91 Mg alloy and its corrosion resistance was compared with those of AZ91 Mg alloy and pure nickel using polarization and electrochemical impedance spectroscopy (EIS) experiments in a 3.5 wt.% NaCl solution. The structure of coating was investigated by means of X-ray diffraction, and the specimen’s morphology and the coating’s chemical composition were analyzed using scanning electron microscope (SEM). The results showed that the coating has a nano-crystalline structure with the average grain size of 95 nm. The results of corrosion tests showed a decrease in the corrosion current density from 2.5×10-4 A.cm-2 for the uncoated sample to 1.5×10-5 A.cm-2 for the coated specimen, as well as an increase in the corrosion potential.

کلیدواژه‌ها [English]

  • AZ91 Mg alloy
  • Nickel electrodeposition
  • corrosion
  • EIS
  • Polarization
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