用系列冲击试验,AES和SEM分析研究了CuP耐大气腐蚀钢中P的偏聚行为,钢中添加稀土后断口形貌的变化及对钢韧性的影响。结果表明,钢中加入稀土,可净化晶界,断口形貌由沿晶断裂向穿晶断裂过渡,提高韧性。CuP钢中确有P沿晶界偏聚。添加稀土后,晶界P偏聚减少,是钢韧性提高的重要原因,但P的偏聚尚未完全消失。 A series of impact tests, AES and SEM were used to study the segregation behavior of P in CuP weathering steels, the change of the fracture morphology after the addition of rare earth in steel, and the influence on the toughness of the steel. The results show that the addition of rare earth in steel can purify the grain boundary, and the fracture morphology transitions from intergranular fracture to transgranular fracture to improve the toughness. CuP steel does have P along the grain boundary segregation. Adding rare earth, grain boundary P segregation decreases, the toughness of steel is an important reason to improve, but the segregation of P has not completely disappeared.