Sestavení DCCT diagramu oceli AISI 4130 po vysokoteplotní austenitizaci

Abstract

This thesis is focused on construction of DCCT wich is describing phase transformations of AISI 4130 steel. Austenitization parameters are specific in this work, because it was done in temeperature of 1280 °C. This was done to simulate heating of entering material for penetrating by slant rolling. DCCT diagram itself was constructed on data taken from number of dilatometric tests in combination with matalographic tests and hardness tests. As a result of this experiment was found that, combination of high temperature austenitization and pre-deformation have a significant influence on final structure. Structure that has a bigger grains thanks to high temperature and deformation leads to creation of acikular ferrite and bainite mixture in wide range of cooling rates in investigated steel.