Development of ultra-fine grained steels by controlling peritectic and inverse eutectoid reaction processes

本研究的目的是通过控制凝固和热处理条件来获得具有非常细小的奥氏体晶组织的碳钢，而不需要变形。从理论、模拟和实验等方面详细研究了添加Ti、V、Nb以及不同的冷却和加热条件对晶粒组织的影响，阐明了细化晶粒的最佳条件。结果表明，金属型铸造-快速加热工艺制备的含钛碳钢组织细小，平均尺寸为1微米左右。

The purpose of this study is to obtain carbon steels exhibiting very fine austenite grain structures by controlling solidification and heat treatment conditions without the deformation processes. Effects of Ti, V, and Nb additions, different cooling and heating conditions on the grain structure were investigated in detail by means of the theories, simulations and experiments to elucidate optimal conditions for the grain refinement. It was found that the carbon steel with Ti addition fabricated by permanent mold casting followed by rapid heating process exhibits very fine grain structure, the average size of which is as small as about 1 micron.