The effects of a slow heating rate and a long austenitizing time with various cooling rates on the carbide dissolution and phase transformations of a 5% Cr work roll steel was investigated based on actual austenitization and quenching conditions and a large roll size using transmission and scanning electron microscopy, dilatometry, and thermodynamic calculations. When the roll temperature reached the austenitization temperature of 1173K, the dissolution of pre-existing carbides was nearly complete due to the slow heating rate of 100 K/h, indicating that the austenite matrix had an equilibrium chemical composition at 1173K before quenching. After quenching at cooling rates ranging from 0.1 to 3.0 K·s -1 along the radial direction of the roll, the core of the roll contained ferrite, pearlite, bainite and undissolved carbides, while the surface consisted of martensite and undissolved carbides.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering