Boron influence on the development of Laves phase in 10Cr creep resistant steel

Abstract

• Enhanced boron content refines precipitating Laves phase. • Laves phase content remains the same. • Enhanced boron content causes formation of thin Laves phase films. • The films does not cause loss of plasticity at 650 °C. The evolution and coarsening of Laves phase in 10Cr-3W-3Co-1Mo nitrogen free creep resistant steels at temperature 650 °C was quantified by use of scanning electron microscopy and image analysis. Influence of B was followed by comparison of two experimental steels with 90 ppm and 120 ppm of B. Results showed the refining influence of enhanced B content on the Laves phase evolution and the formation of thin Laves phase films due to higher B content. Quasistatic tensile tests at temperature 650 °C did not show detrimental effect of these films on the material plasticity.