Abstract
Two different coatings of 1100 aluminium were cold sprayed onto similar substrates, using He and He–20N2 (vol.-%) mixture as carrier gases. Three point bend testing was carried out. The elastic moduli of the coatings were found to be close to each other and the substrate. The He processed coating showed higher fracture strength which was attributed to the higher degree of strain hardening. The He–20N2 processed coating failed at lower stress owing to its strain relaxed structure. The mode 1 fracture of the coating substrate system was found to be higher for the helium processed coating. The toughness was correlated to the microstructure. The delaminated coating showed a higher degree of brittle failure of the interface for the He processed coating.