بررسی مورفولوژی و رفتار خوردگی پوشش الکترولس Ni-P بر روی آلیاژ Mg-7Li با استفاده از پیش عملیات‌ مختلف

نوع مقاله : علمی و پژوهشی

نویسندگان

• محمد قادری ¹
• سید محمود منیرواقفی ²

¹ دانشگاه آزاد اسلامی واحد نجف آباد

² دانشگاه صنعتی اصفهان

10.22067/ma.v0i29.43707

چکیده

در این پژوهش، مورفولوژی، خواص مکانیکی و خوردگی پوشش الکترولس Ni-P توسط پیش عملیات مختلف بر روی آلیاژ Mg-7Li (MA21) مورد مطالعه قرار گرفت. نتایج نشان می‌دهد که افزودن 125 گرم بر لیتر کروم تری‌اکسید (CrO3) و 110 میلی‌لیتر بر لیتر اسید نیتریک (HNO3) به محلول اسیدشویی می‌تواند منجر به افزایش یکنواختی لایه میانی و کاهش تخلخل پوشش الکترولس ‌شود. یکنواختی لایه LiF و MgF2 منجر به افزایش تعداد مکان‌های جوانه‌زنی پوشش شده و مورفولوژی ظریف را ایجاد می‌کند. نرخ خوردگی نمونه MA21، نمونه با پوشش الکترولس Ni-P با دو پیش عملیات CrO3: 180 g/l, KF: 1g/l (شماره 1) و CrO3: 125 g/l, HNO3: 110 ml/l (شماره 2) به ترتیب 63، 87 و 4 میلی-اینچ در سال بدست آمد. نتایج آزمون چسبندگی پوشش الکترولس با پیش عملیات شماره 2 حدود 2 برابر نسبت به پیش عملیات شماره 1 افزایش یافته است.

کلیدواژه‌ها

• Mg-7Li
• پوشش الکترولسNi-P
• پیش عملیات
• خواص خوردگی
• خواص چسبندگی پوشش

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عنوان مقاله [English]

Investigation of Morphology and Corrosion Behavior of Electroless Ni-P Coating on Mg-7Li Alloy with Different Pre-treatments

نویسندگان [English]

• Mohammad Ghaderi ¹
• Seyyed Mahmoud Monir Vaghefi ²

¹ Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad, Iran

² Isfahan University of technologhy

چکیده [English]

In this study, morphology, mechanical and corrosion properties of Ni-P electroless coating was investigated using different pre-treatments on the Mg-Li (MA21) alloy. The results show that adding 125 g/l chromium trioxide and 110 ml/l nitric acid to the pickling solution can increase the uniformity of the intermediate layer and reduce the porosity of the Ni-P electroless coating. The MgF2 and LiF layer uniformity leads to the increase in the number of coating nucleation sites and a fine morphology. The corrosion rate of the MA21 sample, Ni-P electroless coating sample with 125 g/l CrO3 and 110 ml/l HNO3 was 63, 87 and 4 mpy, respectively. The test results of Ni-P electroless coating adhesion with pretreatment number 2 was double that of pretreatment number 1.

کلیدواژه‌ها [English]

• Mg-7Li, Electroless Coating
• Ni-P
• Pre-Treatment
• Corrosion Properties
• Coating Adhesion Properties

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