Laser power influences the range of dilution with the substrate and thus, the microstructure and properties of the coatings. This work evaluated the effect of laser power on the dilution, microstructure, hardness and wear behavior of Hastelloy C276 TM alloy coatings deposited on AISI 304L stainless steel and GGG40 ductile iron. The microstructure was comprised of γ (Ni-FCC) dendrites and molybdenum-rich interdendritic regions containing carbides. The coatings showed similar second phase nature and fraction and equivalent hardness and wear behavior for the lowest laser power condition. Otherwise, higher power on 304L induced to a lower fraction of blocky-like M 23 C 6 /MC carbides; whilst on GGG40 led to a higher fraction of a predominantly lamellar M 6 C type carbide. Largely diluted coatings on ductile iron entailed differences in the strengthening mechanisms which led to higher hardness and lower wear rate. Moreover, wear tracks showed surface oxidation which in turn negatively influenced the performance of specimens with low dilution on both substrates. On the other way, with high dilution, this feature was only observed on stainless steel.

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The class of imidazolium salts contains effective anticorrosion additives for metal substrates. This study evaluated the potential of 1-carboxymethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide (HO 2 CC 1 MImNTf 2) for application in cultural heritage, exploring it as anticorrosion additive in chitosan-based coatings for the protection of copperbased alloys. Under accelerated corrosion conditions with HCl vapor, the chitosan coating with HO 2 CC 1 MImNTf 2 was less effective than the one with benzotriazole. The coating with a combination of HO 2 CC 1 MImNTf 2 and benzotriazole resulted in the optimal protective efficacy of the bronze surface, and it also maintained high transparency without changing the bronze appearance.

In order to protect industrial components, cobalt base alloys are applied as hardfacing material through welding techniques. A large number of papers have shown that controlling the chemical composition is a key point regarding the wear and corrosion resistance of coatings. This paper investigated the effect of bead overlapping on the microstructure and properties of CoCrWC alloy coatings. Mechanical properties were determined by hardness, sliding wear and microtensile tests. Bead overlapping reduces dilution during the previous bead melting, which in turn induces lower iron content. From the second bead on, an increase in the amount of interdendritic carbides and solid solution alloying was verified, accounting for the higher mechanical properties of the coatings.

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