بهبود ترک‌پذیری در پوشش‌های تبدیلی بر پایه عناصر خاکی کمیاب

نوع مقاله : مقاله مروری

نویسندگان

1 محقق دکترا، گروه پوشش‌های سطح و خوردگی، پژوهشگاه رنگ، تهران، ایران، صندوق‌پستی:654-167665.

2 دانشیار، گروه روکش‌های سطح و خوردگی، پژوهشگاه رنگ، تهران، ایران، صندوق‌پستی:654-167665.

چکیده

محافظت در برابر خوردگی فلزات، سال‌‌‌ها دغدغه‌‌‌ی پژوهشگران بوده است. در نتیجه برای گسترش کاربرد فلزات، از روش‌‌‌های گوناگونی برای افزایش مقاومت به خوردگی آن‌‌‌ها استفاده می‌‌‌شود. در این پژوهش، از میان فناوری‌‌‌های اصلاح سطحی، پوشش‌‌‌های تبدیلی به دلیل تشکیل رسوب یکنواخت بر روی سطح فلز، بهبود چسبندگی لایه‌‌‌ی اعمالی بعدی، کاربری آسان و به‌‌‌صرفه بودن، بیشتر مورد توجه قرار گرفته است. همچنین این پوشش‌‌‌ها مانند یک سد فیزیکی میان زیرلایه و محیط عمل می‌‌‌کنند و علاوه بر محافظت در برابر خوردگی، با افزایش انرژی سطحی، چسبندگی پوشش‌‌‌آلی به زیرآیند فلزی را بهبود می‌‌‌بخشند. در سال‌‌‌های اخیر تلاش شده است تا با اضافه نمودن انواع افزودنی‌‌‌ها، ویژگی‌‌‌های پوشش‌‌‌های تبدیلی بر روی سطوح فلزی بهبود داده ‌‌‌شود. در این راستا افزودنی‌‌‌ها به صورت عناصر خاکی کمیاب (به دلیل سازگاری با محیطزیست) به پوشش تبدیلی افزوده شدند تا مقاومت آن را در برابر خوردگی افزایش دهد. اما عیب بزرگ این پوشش‌‌‌ها، تشکیل ترک در پوشش نهایی است. بنابراین، در این تحقیق، به بررسی راه‌‌‌حل برای ازبین‌‌‌بردن ترک در پوشش‌‌‌های تبدیلی، پرداخته شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Crack Modification in Rare Earth Based Conversion Coatings

نویسندگان [English]

  • Seyed Ali Nezamzadeh 1
  • Reza Amini 2
  • Pooneh Kardar 2
1 Surface coating and Corrosion Department, Institute for Color Research and Technology, P. O. Box: 16765-654, Tehran, Iran.
2 Surface coating and Corrosion Department, Institute for Color Research and Technology, P. O. Box: 16765-654, Tehran, Iran.
چکیده [English]

Corrosion protection of metal substrates has been a researcher's concern for many years. Accordingly, various techniques are used to enhance the functionality of metals and improve their resistance. This research focused on conversion coatings due to their uniform film formation on metal surfaces, better interlayer adhesion, and easier application. These coatings act as a physical barrier between the substrate and the environment, and in addition to protecting against corrosion, by increasing surface energy, they improve the organic coating's adherence to the metal substrate. In recent years, many attempts have been made to upgrade the conversion coating's properties on metal surfaces by adding various additives. In this regard, additives in the form of rare earth elements (due to compatibility with the environment) were added to the conversion coating to increase its resistance to corrosion. However, the main issue with these coatings is producing small cracks in the final coating. Therefore, in this paper, the approach is to eliminate the cracks investigated.

کلیدواژه‌ها [English]

  • Anticorrosive coatings
  • Conversion coatings
  • Rare earth elements
  • Surface treatment
  • Gelatin
  • Chitosan
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