High boron cast steel material and preparation method thereof

Abstract

The present invention discloses a high-boron cast steel material that is resistant to corrosion and wear from high-temperature molten aluminum, and a method for preparing the same. The composition (wt.%) of the material includes 0.1-1% C, 1.0-6.5% B, 7.5-25% Cr, 0.5-12.5% ​​Mo, 0.5-3.5% Si, 0.5-8.5% Al, 0.2-1.2% Mn, less than 0.05% S, less than 0.05% P, and the balance Fe. The method includes the steps of annealing the resulting casting, followed by quenching and tempering. The material structure prepared by the present invention is composed of a martensite matrix phase, rod-shaped and network-shaped Cr-rich boride phases, and irregular block-shaped Mo-rich boride phases. It has a room temperature hardness of 36.5 to 61.0 HRC, an impact toughness of 2.5 to 8.0 J / cm2, and corrosion and wear rates in high-temperature molten aluminum at 750°C that are 2.0 to 9.0 times lower than those of H13 steel.