We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Microstructure and Micromechanical Response in Gas-Atomized Al 6061 Alloy Powder and Cold-Sprayed Splats.
- Authors
Bedard, Benjamin A.; Flanagan, Tyler J.; Ernst, Alexis T.; Nardi, Aaron; Dongare, Avinash M.; Brody, Harold D.; Champagne, Victor K.; Lee, Seok-Woo; Aindow, Mark
- Abstract
Gas-atomized Al 6061 powder was studied in as-atomized, heat-treated, and homogenized conditions, and low-coverage cold spray deposits were produced from these powders to allow individual splats to be investigated. The microstructures were investigated by electron microscopy, and the mechanical behavior of the particle/splat interiors was evaluated by the compression of micropillars milled from the samples. The as-atomized and heat-treated powders exhibit cell-like solidification microstructures with Mg-Si and Fe-Al-Si secondary phases around the cell boundaries. These powders have flow stresses of ≈ 185 MPa with pronounced strain bursts due to rapid, stochastic dislocation motion confined within the cells. In the homogenized powders, the Mg-Si phase has dissolved, the Fe-Al-Si has coarsened, and the grain boundaries have unpinned. The stress-strain curves are smoother due to the dissolution of cell boundary obstacles, but the flow stress is about 30 MPa higher due to the increased solute content giving more sluggish dislocation motion. The microstructures of the splat interiors resemble those of the powders closely, but the flow stresses measured are all much higher (280-290 MPa) with little effect of powder microstructure or deposition pressure. This is consistent with the high dislocation density reaching a saturation value in all of the splats studied.
- Subjects
MICROSTRUCTURE; HEAT treatment; METAL coating; STRAINS &; stresses (Mechanics); MICROMECHANICS
- Publication
Journal of Thermal Spray Technology, 2018, Vol 27, Issue 8, p1563
- ISSN
1059-9630
- Publication type
Article
- DOI
10.1007/s11666-018-0785-0