Effect of Continuous Cooling Conditions on Microstructure and Mechanical Properties of High Carbon Steel Rod

The effect of cooling rate and austenitizing condition on the mechanical properties of high carbon steel (SWRH82B) has been investigated. Specimens were made of high carbon steel rod and heat-treated by Gleeble-2000 to produce a wide variation in prior austenite size. Different cooling rates were carried out, and then pearlite interlaminar spacing and mechanical properties were measured and tested respectively. According to the results, it could be found that under the continuous cooling with the increase of cooling rate, tensile strength greatly increases and reduction in area exhibits a slightly increase for an equivalent value of prior austenite grain size. When prior austenite size increases, reduction in area decreases, and tensile strength increases slightly for an equivalent value of pearlite interlaminar spacing. It is concluded that prior austenite size primarily controls ductility and pearlite interlaminar spacing controls tensile strength. Mathematical formulae are given for these relations.