Finishing of thermally sprayed metallic, ceramic, and cermet coatings is required to meet tolerances and requirements on surface roughness in most industrial applications. Conventional machining is a costly and time-consuming process, and is difficult to automate. Therefore, this study investigates and develops a new technique highly amenable for automation: fast regime-fluidized bed machining (FR-FBM). Atmospheric plasma sprayed TiO 2, Cr 2O 3, and HVOF-sprayed WC-17%Co and Tribaloy-800 coatings, deposited on AISI 1040 steel substrates, were subjected to FR-FBM treatment. The effects of the leading operational parameters, namely, abrasive size, jet pressure, and processing time, were evaluated on all coatings by using a two/ three-levels full factorial design of experiments. The FR-FBM treated surfaces were observed by FE-SEM and their surface finishing was evaluated by contact profilometry. Significant improvements in surface finishing of all the machined thermally sprayed coatings can always be detected, with FR-FBM being able to guarantee the precision and to ensure the closest geometrical tolerances. © ASM International 2008.
Barletta, M., Rubino, G., Bolelli, G., Lusvarghi, L. (2008). Fast regime fluidized bed machining (FR-FBM) of thermally sprayed coatings. JOURNAL OF THERMAL SPRAY TECHNOLOGY, 17(5-6), 796-804 [10.1007/s11666-008-9266-1].