Effect of working voltage on the mechanical/corrosion properties of Ni-SiO2-PTFE nanocomposite deposition layer on the inner wall of pipeline

A Ni-SiO2-PTFE nanocomposite deposited layer was successfully prepared on the inner wall of the pipe by nanobrush plating method. The influence of the working voltage (10 V, 12 V, 14 V, 16 V, 18 V) on corrosion and mechanical properties of Ni-SiO2-PTFE deposited layer was investigated. Using SEM (2.000 x) and EDS (2.000 x) analysis, the surface of the deposited layer appeared smooth and dense at a working voltage of 14 V. Simultaneously, the maximum fluorine (F) content was found to be 0.62%. The analysis of nanoindentation experiment (6.25 mN, 12.5 mN, 25 mN, 50 mN, 100 mN) reveals that the maximum elastic recovery ratio (he/ hmax) of the deposited layer was 0.30 and the fracture toughness ratio (H3/E2) reached a peak value of 0.019 at a working voltage of 14 V. Using a metallographic microscopy (1.000 x) analysis, the thickness of the deposited layer reached a maximum of 7.36 mu m at a working voltage of 14 V. Using a Vickers hardness tester (15 g) analysis, the hardness of the deposited layer reached a maximum value of 538 HV at a working voltage of 14 V. Using an electrochemical workstation (3.5 wt% NaCl, 25 celcius) analysis, it was discovered that at a working voltage of 14 V, the corrosion potential of the deposited layer reached its maximum at - 0.71 V, and the corrosion current density reached its minimum at 1.92 x 10-5 A & sdot;cm- 2. Experimental results show that the deposited layer has the best corrosion and mechanical properties when the working voltage is 14 V.