本文探讨了σ_b≥850MPa的Cr-Mo-Mn-Si系熔敷金属中加稀土(Re)硼(B)和微量硼对冲击韧性的影响。研究表明,加入适量的Re要比单独加B更为理想,尤其是对低温冲击韧性而言。这主要是Re能改变夹杂物的形态以及自身形成高熔点的细小夹杂物,分布在晶界与B联合强化的缘故。 In this paper, the effect of addition of rare earth (Re) boron (B) and trace boron on the impact toughness of Cr-Mo-Mn-Si system deposited on σ_b≥850MPa was investigated. Research shows that adding an appropriate amount of Re is better than adding B alone, especially for low temperature impact toughness. This is mainly due to Re can change the morphology of inclusions and their formation of high melting point of small inclusions, distributed in the grain boundary and B strengthen the reason.