镍、铬对高强钢金属粉型药芯焊丝熔敷金属组织与性能的影响

Effect of Ni and Cr on the microstructure and properties of deposited metal with metal cored wire of high strength steel

向金属粉型药芯焊丝配方中添加不同含量的Ni、Cr,研究其对高强钢熔敷金属组织与性能的影响。结果表明:Ni、Cr对熔敷金属的强度、塑性与低温冲击韧性影响程度不同。Cr含量不变时,随着熔敷金属中Ni含量从2.78%增加到3.38%,针状铁素体、马氏体增多,贝氏体、侧板条铁素体含量减少,熔敷金属的强度和韧性变化不大,但塑性下降;Ni在提高抗拉强度方面作用有限,添加Cr可以进一步提高强度,但过量的Cr会造成韧性下降。在w(Ni)2.90%、w(Cr)0.45%时,以条状贝氏体为主的熔敷金属强度高、塑韧性好,综合力学性能最佳。

The effects on the microstrueture and properties of deposited metal of high strength steel were investigated by adding different contents of Ni and Cr powder to the flux cored wire. The results indicated that the content of Ni and Cr has a considerable effect on the strength and the impact toughness of deposited metal. The content of acicular ferrite and martensite increases while the content of bainite and ferrite side plates decreases with the addition of Ni increasing from 2.78% to 3.38%. At the same time, there is little change of the strength and the impact toughness, but the plastic has dropped significantly. Ni has limited effect on enhancing the tensile strength, so Cr is needed but exlessive amounts of Cr will cause the loss of resilience. The excellent combination of mechanical occurred when the content of Ni is 2.90% and Cr is 0.45% ,the microstructure of its deposited metal is consist of lath bainite mainly.