Abstract
Little attention has been paid to the way in which the isothermal transformation characteristics of steel may vary with variations in austenitizing treatment. Therefore, we studied the influence of austenitizing degree on the mechanical properties after completion of isothermal transformation of 0.68% carbon steel by means of tension-and-bending test. The progressing degree of austenizing and the homogeneity of the austenite greatly affected the mechanichal properties, in particular the tensile strength and the area contraction, after isothermal transformation of these steels. Insufficient austenizing treatment of the specimens results in inferior tensile-and-the bending properties. In the specimens incompletely austenized, the lower bainite formation process in isothermal transformation of the specimens of spheroidized pearlites differs from that of the specimens with lamellar pearlitic structure.
