The effect of low tempering in a temperature range of 150-400℃ on corrosion resistance in 42OJ2 stainless steel austenitized at 1000℃ was investigated by the application of salt spray test, electrochemical pitting test in 3.5% NaCl solution and DL...
The effect of low tempering in a temperature range of 150-400℃ on corrosion resistance in 42OJ2 stainless steel austenitized at 1000℃ was investigated by the application of salt spray test, electrochemical pitting test in 3.5% NaCl solution and DL-EPR test for intergranular corrosion in 0.5M H₂SO₄+0.01 M KSCN solution. In salt spray test, good corrosion resistance was obtained in a tempering temperature range of 150-250℃. Pitting potential was increased to the tempering temperature of 250℃, but decreased with the increase of temperature up to 400℃ And it was thought that the degradation of pitting corrosion resistance showed at the tempering temperature of around 400 C was due to the precipitation of Cr^(7)C₃of M^(7)C₃ type. The degree of sensitization showed increasing tendency with the increase of tempering temperature, and also Cr depletion phenomena were observed in the vicinity of grain boundary.