effect of continuous annealing with different cooling rates on microstructural characteristics and mechanical properties of ultrafine carbide-free bainite in high-carbon stee

In addition to conventional isothermal heat treatment, ultrafine carbide-free bainite can be obtained by continuous annealing of steels, which is of great interest to scientists and research communities. the resulting microstructure consists of bainitic sheaves composed of bainitic ferrites interwoven with austenite films both in nanoscale, being separated by austenite micro blocks resulting in gpa-strength level. this article aims to investigate the microstructural characteristics and impact toughness of high-carbon steel after continuous cooling heat treatment at cooling rates of 0.1, 0.15, 0.2 and 0.3 °c/min. results illustrate that bainitic ferrites and austenite films of less than 270 nm austenite could be attained