Effects of Chemical Composition and Microstructure on the Free Corrosion Potential of Pure Titanium

Chemical composition, microstructure and corrosion potential in seawater of the base metal and two kinds of TA2 titanium plate prepared by automatic welding and manual welding were analyzed. The results showed that the free corrosion potentials of automatic welding seam sample, manual welding seam sample and base metal sample had a little difference. The content of gas elements (C, N) of base metal sample and weld metal sample were different. The microstructure of base metal is a single equiaxed α phase, while the weld is a thick, serrated α phase and a small amount of needle martensite. The effects of chemical composition and microstructure on self corrosion potential of 3 samples in seawater are little.