Grain boundary segregation of B and microstructure evolution in a hot-drawn Fe-B alloy

The grain boundary segregation (GBS) of boron and microstructure evolution in a hot-drawn Fe-B alloy are investigated utilising the Gleeble-1500, Auger electron spectrometer, time-of-flight secondary ion mass spectrometry, electron back-scattered diffraction, and transmission electron microscopy techniques. The results suggest substantial boron segregation at grain boundaries of the Fe-B alloy during the hot drawing process. In comparison to the contribution of dislocations to boron diffusion coefficients, the influence of vacancies is predominant. With the increase in hot-drawing temperature, the ratio of excess vacancy content to thermal equilibrium vacancy content C e x / C t h decreases, and the content of low & sum; CSL (low Sigma coincidence site lattice) boundaries increases, resulting in a reduction in boron GBS content. Additionally, elevating the hot-drawing temperature promotes dynamic recrystallisation and refines the grains. The volume fraction of the <110>//RD (rolling direction) texture component initially increases and then decreases with increasing temperature, reaching a maximum value of 64.6% at 830 degrees C, while the percentage of the <100>//RD + <111>//RD texture components exhibits the opposite trend, with a peak value of 27.4% observed at 1000 degrees C.