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  • Post-Fire Analysis of Thermally Sprayed Coatings: Evaluating Microstructure, Mechanical Integrity, and Corrosion Behavior
Title: 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.  more » « less
Award ID(s):
2119691 1750316
PAR ID:
10422257
Author(s) / Creator(s):
; ; ;
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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