Ultrasonic Consolidation Post-Treatment of CuNi:Cr3C2-NiCr Composite Cold Spray Coatings: A Mechanical and Microstructure Assessment

• Published in: Journal of thermal spray technology Vol. 30; no. 8; pp. 2069 - 2082
• Main Authors: Brown, Robert F., Smith, Gregory M., Hehr, Adam, Eden, Timothy J.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2021
• Subjects: Analytical Chemistry; Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Machines; Manufacturing; Materials Science; Peer Reviewed; Processes; Surfaces and Interfaces; Thin Films; Tribology; C; microstructure; cold spray; ultrasonic consolidation; CuNi; mechanical properties; Cr; NiCr
• ISSN: 1059-9630; 1544-1016
• DOI: 10.1007/s11666-021-01262-3

The traditional role of cold spray coatings lays in the dimensional restoration of assorted components and machine parts, but these repairs often result in coating mechanical properties that fall short when compared to the parent material. A potential solution to improve mechanical properties, while maintaining the benefits of a complete solid-state process where temperatures remain below the metallic melting point, is by incorporating ultrasonic consolidation as a post-treatment process in conjunction with the cold spray coating. In the work presented here, ultrasonic consolidation was applied upon two metal matrix composite cold spray coatings consisting of mechanically blended feedstock of Cu-38 wt.%Ni and Cr 3 C 2 -30 wt.%NiCr at 50:50 and 25:75 wt.%, respectively. Metallography and mechanical testing were performed to analyze coating response to the ultrasonic consolidation process, which included mean free path relationship of the reinforcing particles (Cr 3 C 2 -NiCr). The results demonstrated an increase in tensile and adhesion properties attributed to the ultrasonic consolidation step, as well as the influence of the increased Cr 3 C 2 -NiCr content. Ultrasonic consolidation applied as a post-treatment upon cold spray coatings was found to provide a unique approach to complete solid-state processing where coating mechanical properties can be improved and/or modified with carbide containing particle content within the metal matrix.