摘要
通过合理的组织、成分设计,采用直接淬火回火(DQ-T)工艺,在实验室成功试制X120级管线钢,并结合金相、透射电子显微技术,研究了不同回火温度对试验钢组织、析出与性能的影响规律。结果表明,随回火温度的升高,屈服强度Rel呈现起伏现象,在450℃和650℃回火后出现两次峰值,抗拉强度Rm变化趋势与Rel相似,起伏相对平缓;冲击功AKv(-20℃)、伸长率A均有一定波动,在450℃回火后,AKv(-20℃)>230 J,A>15%。淬火后450℃回火,钢板为下贝氏体与回火马氏体组织,具有最优的综合力学性能,Rel=845 MPa,Rm=940 MPa,A=16.5%,AKv(-20℃)=236 J,各项指标均符合X120管线钢性能要求。
Through proper chemical composition, microstructure design, adopting DQ-T technology, the X120 line pipe steels were successfully made in laboratory. The relationship among different temper temperature, microstructure, precipitation and mechanical properties was studied by metallography and TEM technology. The results indicate that yield strength Rel, tensile strength Rm, charpy notch impact AKv （ - 20 ℃ ） and percentage enlongation A of the steel fluctuate along with the increase of temper temperature, the steel tempered at 450 ℃ for 1 h consists of fine lath like bainite and temper martensite, the steel has excellent integrated mechanical properties, Rel, Rm, AKv （ - 20 ℃ ） and A reach to 845 MPa,940 MPa,236 J and 16. 5% respectively,every property of the test steel all accord with the X120 standard.
出处
《金属热处理》
EI
CAS
CSCD
北大核心
2007年第10期44-47,共4页
Heat Treatment of Metals
关键词
X120管线钢
显微结构
DQ-T处理
析出
X120 linepipe steel
microstructure
direct quenching and tempering
precipitation
