Hardness and corrosion properties of AA7075 aluminum alloy coated with WC-Co by HVOF

Hasan Hasırcı; Kubilay Karacif

doi:10.1515/mt-2025-0171

Article

Hardness and corrosion properties of AA7075 aluminum alloy coated with WC-Co by HVOF

Hasan Hasırcı
Assoc. Prof. Dr. Hasan Hasırcı, born in 1974, graduated from Gazi University in 1996. He received MSc degree at Gazi University in 2000 and Ph.D degree at Gazi University in 2006. He is currently working as a faculty member in the Department of Metallurgical and Materials Engineering at Gazi University in Ankara. His research areas include cermet coating, heat treatment, wear, casting, and composite materials.
and Kubilay Karacif
Assoc. Prof. Dr. Kubilay Karacif, born in 1972, graduated from Istanbul Technical University in 1994. He received MSc degree at Gazi University in 1999 and Ph.D degree at Gazi University in 2005. Karacif worked as a research assistant at Gazi University in Ankara between 1995 and 2007. He is currently working as a faculty member in the Department of Metallurgical and Materials Engineering at Hitit University in Çorum. His research areas include powder metallurgy, corrosion, composite materials, microstructure, and mechanical properties.

Published/Copyright: August 29, 2025

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From the journal Materials Testing Volume 67 Issue 10

Abstract

In this study, AA7075-T6 aluminum alloy substrates were coated with WC-Co by the high velocity oxy-fuel (HVOF) method. The coatings were applied in two and four layers to surfaces with three different roughnesses. The effects of WC-Co coating applied to the AA7075 aluminum surface on the hardness and corrosion properties of the alloy were examined. The corrosion properties of uncoated and WC-Co coated aluminum alloy samples were determined in salt water environment by potentiodynamic corrosion tests. Additionally, microstructure and XRD examinations of the samples were performed. The surface hardness of WC-Co coated samples increased by up to 140 %. According to the results of corrosion tests, it was determined that the WC-Co coating applied to the surface of AA7075 aluminum alloy improved its corrosion resistance by reducing the corrosion rate of the alloy. The best corrosion resistance was obtained in four layers of coating on the sample with the smallest surface roughness.

Keywords: high velocity oxy-fuel; HVOF; WC-Co coating; AA7075 aluminum; corrosion

Corresponding author: Kubilay Karacif, Metallurgical and Materials Engineering, Hitit University, Corum, 19030, Türkiye, E-mail: kubilaykaracif@hitit.edu.tr

About the authors

Hasan Hasırcı

Assoc. Prof. Dr. Hasan Hasırcı, born in 1974, graduated from Gazi University in 1996. He received MSc degree at Gazi University in 2000 and Ph.D degree at Gazi University in 2006. He is currently working as a faculty member in the Department of Metallurgical and Materials Engineering at Gazi University in Ankara. His research areas include cermet coating, heat treatment, wear, casting, and composite materials.

Kubilay Karacif

Assoc. Prof. Dr. Kubilay Karacif, born in 1972, graduated from Istanbul Technical University in 1994. He received MSc degree at Gazi University in 1999 and Ph.D degree at Gazi University in 2005. Karacif worked as a research assistant at Gazi University in Ankara between 1995 and 2007. He is currently working as a faculty member in the Department of Metallurgical and Materials Engineering at Hitit University in Çorum. His research areas include powder metallurgy, corrosion, composite materials, microstructure, and mechanical properties.

Research ethics: There is no problem in terms of research ethics.
Informed consent: Not applicable.
Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Use of Large Language Models, AI and Machine Learning Tools: None declared.
Conflict of interest: The authors (Hasan Hasırcı and Kubilay Karacif) state no conflict of interest.
Research funding: The study was not financially supported. (None declared).
Data availability: The raw data can be obtained on request from the corresponding author.

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Published Online: 2025-08-29

Published in Print: 2025-10-27

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Articles in the same Issue

https://doi.org/10.1515/mt-2025-0171

Keywords for this article

high velocity oxy-fuel; HVOF; WC-Co coating; AA7075 aluminum; corrosion