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With the wide application of the titanium in the marine field , titanium, and other dissimilar metal contact between the inevitable. The titanium corrosion potential , galvanic corrosion between dissimilar metals , electrical problems will inevitably bring . In this paper, the electrochemical workstation , environmental scanning electron microscopy ( ESEM ) , energy dispersive spectroscopy (EDAX) instruments and galvanic corrosion experiments , analysis of the TA2 industrial pure titanium corrosive under different environmental factors , the researchers TA2 and other piping system materials Galvanic corrosion under different conditions, even direct access law and through the analog electrical insulation test , insulation resistance change of each even the extent of galvanic corrosion , TA2 and the other tube -based materials electrical insulation criterion laid a theoretical foundation for the TA2 industrial pure titanium seawater piping . Experimental results show that when the NaCl concentration of 1.5 % , a pH value of 5 , a temperature of 20 ° C , the samples were immersed in seawater for 240h , TA2 industrial pure generated on the surface of the corrosion product film are the most dense and complete , sample resistance strongest eclipse performance . When the seawater flow rate below 3m / s , TA2 substantially no corrosion occurs ; flow rate higher than 5m / s , TA2 corrosion rate increased by two orders of magnitude . Sand content TA2 corrosive seawater flow rate of 3m / s conditions can affect smaller ; 7m / s , and the amount of sand flow rate of 10 ‰ , TA2 most serious corrosion . TA2 directly with the TUP copper , B10 copper nickel alloy , H62 brass , B30 Copper -nickel alloy seawater piping material even Mate , TA2 as cathode protection , other tube -based materials as anode corrosion acceleration ; TA2 directly even then other piping materials corrosion rate increases as the cathode and anode area ratio increases ; TA2 and the tube -based materials in seawater can not even directly connected galvanic corrosion control measures must be taken . Under the experimental conditions , TA2-TUP and TA2-H62 even static seawater insulation resistance of 56K? Still has some Galvanic Corrosion current density is very small coupling dynamic seawater Galvanic Corrosion can be ignored ; TA2-B10 and TA2-B30 , even between the insulation resistance of 56K? coupling current density is close to zero , the to reach electrical insulation effect .
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