稀土元素Ce对新型616钢板组织和力学性能的影响

摘要

试验的含Ce新型616钢(/％:0.23 ～0.25C,0.73～0.78Si,1.64～1.70Mn,0.003～0.005S,0.016～0.020P,0.051 ～0.061Ti,0.026 ～0.028Nb,0.0020 ～0.003 0B,0 ～0.302Ce)由10 kg真空感应炉熔炼,轧成5 mm厚钢板,并经900℃水淬,600℃回火.通过万能试验机、金相显微镜、扫描电子显微镜等实验仪器研究了钢中Ce含量对616钢板的组织及力学性能的影响.结果表明,当Ce含量在0.096％时,616钢板晶粒细化明显,钢中硫化物由长条状转变为球状,可提高钢板的抗拉强度和韧性,含0.096％ Ce板的抗拉强度从未加稀土的681MPa提高至779 MPa;再增加Ce含量,钢板进一步细化不明显,钢中夹杂物增多,当含Ce 0.302％时,钢板的抗拉强度降至712 MPa.