Ti-Mo-TiC焼結合金におけるTiCの腐食挙動 Corrosion Behavior of TiC in Sintered Ti-Mo-TiC Alloy
The corrosion behavior of TiCx (X=0.55, 0.75, 1.0) and TiC phase in Ti-20mass%Mo-33mass%TiC alloy (TM-2) prepared through P/M technology was studied by corrosion test and electrochemical measurements. The immersion tests in 35%HCl and 3%NaCl solutions showed that the TiC phase in TM-2 alloy and TiCx (X=0.55, 0.75, 1.0) had excellent corrosion resistance in these solutions. The corrosion rates of TM-2 alloy and TiCx (X=0.55, 0.75, 1.0) in 5%HNO<SUB>3</SUB> solution were over 10 times larger than that in 35%HCl solution because of dissolution of the TiC phase. From the potentiodynamic polarization curves, it was thought that the dissolution reaction of the TiC phase in TM-2 alloy and TiCx (X=0.55, 0.75, 1.0) in 5%HNO<SUB>3</SUB> solution was not only an electrochemical reaction, but also a chemical reaction without the electron transfer. The main corrosion of TM-2 alloy was due to the dissolution of a-Ti phase in 35%HCl and 3%NaCl solutions, and the dissolution of TiC phase in 5%HNO<SUB>3</SUB> solution, respectively.
粉体および粉末冶金 46(4), 409-416, 1999-04-15
Japan Society of Powder and Powder Metallurgy