2019 Volume 60 Issue 12 Pages 2537-2541
Continuous cooling transformation of plain high chromium cast irons with Cr/C value from 2 to 15 was investigated using a transformation measuring apparatus with subzero function, and the transformation behavior was clarified. Both AC1 and nose temperature of pearlite transformation (TP-n) rose slightly and its nose time (tP-n) shifted to long time side with an increase in Cr/C value. When the austenitizing temperature was increased, TP-n did not change but tP-n moved to long time side in each Cr/C value. The relationship between tP-n and Cr/C value can be expressed by following equations (1). MS and Mf temperatures rose with increasing Cr/C value and the relations can be expressed by equations below (2). As Cr/C value increased, the maximum hardness after finishing transformation increased to the highest at 6 Cr/C, and then decreased in spite of subzero treatment.
This Paper was Originally Published in Japanese in J. JFS 90 (2018) 224–229.
