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Adsorption and inhibition behavior of 1,2,3-benzotriazole (BTA) and 2,5-dimercapto-1,3,4-thiadiazole (DMTD) on brazing Cu-Ag alloy was studied in deionized water using potentiodynamic polarization measurement, adsorption isotherm investigation and X-ray photoelectron spectroscopy (XPS). Pure Ag and pure Cu were included to investigate the mere effect of each component on the alloy’s behavior. Results show better inhibition of DMTD for Ag and BTA for Cu, both by chemisorption. BTA was found to follow Langmuir isotherm while DMTD obeyed Temkin adsorption isotherm, despite both acting as a mixed type inhibitor. Combining the two inhibitors increased the inhibition efficiency over 80% for the Cu-Ag alloy. XPS spectra demonstrate the formation of DMTD protective film through DMTD’s functional groups of pyrrolic N from the azole ring and thiol S from the mercapto anchoring group on Ag and thiol S on Cu. Compared to BTA, the higher affinity of DMTD to Ag was attributed to the involvement of two heteroatoms with the Ag surface.

Compared to metallic coating, composite coating has more significant mechanical and tribological properties. In this study, titania particles that were codeposited with zinc on a plain carbon steel substrate were used as reinforcements. In addition, the mechanical and tribological properties of these coatings were studied. The effects of bath temperature, stirring rate of electrodeposition solution and concentration of titania in bath on the morphological, mechanical and tribological properties were also investigated. The electrodeposited samples were observed with optical microscope, scanning electron microscope and atomic force microscope. Then, the microhardness and wear properties of the samples were measured. Finally, the optimum degrees of these parameters were achieved to attain maximum codeposition of reinforcement particles, hardness degrees and wear resistance of coatings. The optimised degrees of bath temperature, solution stirring rate and titania concentration in the bath were found to be 40uC, 300 rev min 21 and 5 g L 21 respectively.

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