Effects of Ti Addition on Austenite Grain Growth during Reheating of As-Cast 0.2 mass% Carbon Steel

Abstract

Effects of Ti addition on grain growth in reversely-transformed austenite structure during reheating of the as-cast 0.2 mass% C steel have been investigated for a Ti concentration range between 0 and 0.2 mass% and heating rates from 0.014 to 2.5°C/s. The austenite grain growth during reheating is retarded by the Ti addition and such an effect becomes stronger with the addition of higher amount of Ti. This retarding effect is ascribable to the pinning effect of fine Ti(C,N) particles which should precipitate from the as-cast structure during the reheating process. The experimental results on the grain growth behavior are well explained by the grain growth model including the Zener force and counting reduction of the pinning effect due to the existence of the coarse Ti(C,N) particles crystallized during the solidification.

A role of interfacial energy balance in delta to gamma transformation kinetics in carbon steel with dispersed second phase particles analyzed by phase-field simulation

“…It is based on a retardation effect due to second-phase particles on the migration of d-c interface [3,4]. If the second-phase particles exist in d phase, these particles are expected to retard the migration of d-c interface as is similar to the pinning effect on the grain growth [5][6][7][8][9] and accordingly T c should be lowered. The existence of the retardation effect was found in our previous study on isothermal d to c transformation by a diffusion-couple experiment [3].…”

Phase-Field Simulations and Analysis of Effect of Dispersed Particles on Migration of Delta to Gamma Transformation Interface

“…In this study, we focus on a different way of decreasing T, which is based on a retardation effect of dispersed particles on the migration of - interface. It is well known that the existence of second phase particles in polycrystalline materials retards the migration of grain boundaries, which is called pinning effect [7][8][9][10] . The origin of the pinning effect corresponds to the reduction of the total grain boundary energy due to the intersection of the boundary with the particles.…”

Effect of Interdendritic Impurity Segregation on Hot Ductility Behavior of Low‐Carbon Steels

“…MC and MN effectively constrain grain growth by pinning grain boundaries at high temperatures. [ 17–20 ]…”

“…MC and MN effectively constrain grain growth by pinning grain boundaries at high temperatures. [17][18][19][20] Especially, the equilibrium TiN formation temperature of Steels A and B is 1437 and 1227 C, respectively, which is calculated using Thermo-Calc with the TCFE9 database ( Figure 12). As the TiN formation temperature (1437 C) of Steel A is higher than the re-heating temperature (1350 C), the full dissolution of TiN does not occur in RHT.…”