Impact of boron on melt properties and structurization of iron and nickel-based steels and alloys

Direct fabrication of high-performance high speed steel products enhanced by LaB 6

“…Commonly, the active boron atoms dissolved into matrix are able to stabilize undercooled austenite [46] and improve the hardenability of steel [21,22,44] resistance and hardness contributed by boron have been reported [22]. The harder boro-carbides may partially contribute to the red hardness increasing with LaB 6 content.…”

“…Minor LaB 6 was particularly introduced into DFT steels, preliminarily aiming at strengthening grain boundaries (GBs) by boron segregation [21][22][23][24][25] and simultaneously purifying the steel via the absorbing effect of rare earth (RE) complexes [18,19]. During smelting, the accurate and lossless additions of high melting elements and the elements sensitive to oxidation, such as boron [20][21][22][23] and RE [18,19], are always tough puzzles.…”

“…During smelting, the accurate and lossless additions of high melting elements and the elements sensitive to oxidation, such as boron [20][21][22][23] and RE [18,19], are always tough puzzles.…”

“…It means the non-equilibrium segregation of boron along vacancy sinks (i.e. grain boundaries), which commonly occurs in boron containing steels during cooling [18,21,44], are not detected in the as-tempered DFT 10LB. Similarly, Keown [45] also stated that no boron segregation occurs in Cr-Mo-V creep-resisting steel after tempered at 700℃, though Karlsson [18] demonstrated that boron atoms are very mobile and segregate even after cooled from below 500℃.…”