Friction surfacing technique is a thermo-mechanical approach for metallic deposition, suitable for a broad range of materials and applications. Friction surfacing can be employed for various industrial purposes such as coating, welding, repairing defective parts, surface hardening, and improving corrosion performance. In this technique, frictional heat generated at the interface of the consumable tool and substrate results in a severe plastic deformation at the end of the rod, enabling the deposition of a consumable material on the substrate surface.
In this investigation, a novel method in friction surfacing, lateral friction surfacing, is employed to deposit the aluminum coatings. In this novel approach, the side of the consumable tool is pressed against the surface of the substrate, and the material transfer happens from the lateral surface of the tool. This technique provides extremely thin and smooth deposits, which are more consistent compared to the conventional approach of friction surfacing. Moreover, this technique enables fabricating of deposits in lower temperatures, lessening the thermal impacts on the microstructures and mechanical properties of the deposits.
In this investigation plates of 1018 mild steel were partially coated with various aluminum alloys and corroded in an accelerated corrosion test chamber. The corrosion performance of the partially coated sample was evaluated by mass loss measurement. It was found that AA5086 offered the most corrosion protection. After 13 cycles of GM9540P test, equivalent to approximately 3½ years exposure at a mild/moderate marine site in Hawaii, almost all of the deposited aluminum was consumed.
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This content will become publicly available on May 1, 2024
Post-Fire Analysis of Thermally Sprayed Coatings: Evaluating Microstructure, Mechanical Integrity, and Corrosion Behavior
This paper examines the impact of fire on the microstructural, mechanical, and corrosion behavior of wire-arc-sprayed zinc, aluminum, and Zn-Al pseudo-alloy coatings. Steel plates coated with these materials were subjected to temperatures in increments of 100 °C, starting from 300 °C and progressing until failure. Microstructural characterization, microhardness, abrasion resistance, and electrochemical impedance studies were performed on the post-fire coatings. The findings from this study show that heat had a positive impact on the performance of zinc and Zn-Al pseudo-alloy coatings when they were exposed to temperatures of up to 400 °C, while aluminum coatings maintain their performance up to 600 °C. However, above these temperatures, the effectiveness of coatings was observed to decline, due to increased high-temperature oxidation, and porosity, in addition to decreased microhardness, abrasion resistance, and corrosion protection performance. Based on the findings from this study, appropriately sealed thermal-spray-coated steel components can be reused after exposure to fire up to a specific temperature depending on the coating material.
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- NSF-PAR ID:
- 10422257
- Date Published:
- Journal Name:
- Processes
- Volume:
- 11
- Issue:
- 5
- ISSN:
- 2227-9717
- Page Range / eLocation ID:
- 1490
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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