Effect of thermal treatment on the interfacial reaction, microstructuraludand mechanical properties of Zn–Al–SnO2/TiO2 functional coating alloys

摘要

In this paper, the microstructure and thermal treatment behavior of Zn–Al–SnO2/TiO2(Zn–Al–Sn/Ti)udproduced through co-deposition route was investigated. 7.0–13.0 wt% TiO2 and SnO2 was added toudZn–Al bath. Thermal treatment was done for 2 h at 200 �C, 400 �C and 600 �C. The ageing characteristicsudof the coated alloys were evaluated using (SEM/EDS) and XRD. The hardness and wear value of the thinudfilm were examined with micro-hardness and UMT-2 sliding tester respectively. The corrosion propertiesudwere evaluated by linear polarization in 3.65% NaCl. From the result obtained, the coating exhibited goodudstability. The uniform distribution of the composites on the fabricated alloy and age-treatment were theudmajor factor responsible for the mechanical and electrochemical improvement. The optimum value wasudobtained at Zn–Al–7Sn–Ti–0.3V–S for as-coated and Zn–Al–7Sn–Ti–0.3V–S at 400 �C for the thermal-agedudsamples. The stabilities in hardness and corrosion resistance against the working substrate were attributedudto the formation of coherent and uniform precipitation in the metal lattice