2020 Volume 61 Issue 1 Pages 169-175
The influence of alloying elements on continuous cooling transformation (CCT) behavior was investigated for 16 mass% chromium cast irons containing 0.9 to 4 mass% Mo, V and Nb separately using a transformation measurement apparatus with subzero cooling function. On CCT curves, pearlite and martensite transformations appeared irrespective of the type of alloying element. When Mo was added by more than 1 mass%, bainite transformation was observed in addition to the two transformations above. Regardless of the type of alloying elements, pearlite transformation delayed when the amount of each alloying element was increased. It was found that Mo addition was most effective for delaying pearlite transformation in these alloying elements. MS and Mf temperatures increased slightly by increasing V and Nb contents. Both temperatures decreased with the addition of Mo up to 2 mass% and increased with the addition of Mo over 2 mass%. Regardless of the type and amount of alloying elements added, pearlite transformation delayed, and MS and Mf temperatures decreased with increasing austenitizing temperature.
This Paper was Originally Published in Japanese in J. JFS 90 (2018) 373–380. Figures 2–4, 12 and 15 were slightly changed.