Evolution of boron segregation during tempering in B doped 9%Cr ferritic steel

Boron segregation behavior during tempering at 600 and 790 °C was examined in a boron-doped 9Cr-steel by using high-resolution SIMS imaging (nano-SIMS). Boron segregation that developed at prior austenite grain boundaries (PAGBs) during austenitizing was found to decrease reduced during tempering because the equilibrium concentration of B segregation for austenite is larger than that for ferrite so that the segregated boron atoms diffused into...