TP310HCbN耐热钢Ф47mm×8mm管材700℃持久试验析出行为

Behavior of Precipitation in Φ47 mm×8 mm Tube of Heat Resistant Steel TP310HCbN during Rupture Test at 700 ℃

通过扫描电镜、透射电镜、能谱分析和硬度试验等方法分析了TP310HCbN耐热钢（/%：0.07C,0.39Si,1.20Mn,25.05Cr,20.40Ni,0.42Nb,0.266N）φ47mm×8 mm冷轧管经1 120~1 160℃固溶处理后在700℃0~19 570 h持久试验时的析出相。结果表明,TP310HCbN耐热钢700℃95~220 MPa持久试验时间在0~1 000 h时,随时间增加,硬度HV值由237增至255,当持久时间超过1 000 h,硬度趋于平稳;随着持久时间增加,该钢晶内析出物由颗粒状转变为棒状,并存在大量与位错相互作用的蠕虫状NbCrN析出物;生产的TP310HCbN耐热钢700℃-100 000外推持久强度为63.65 MPa满足标准要求。

The precipitated phases in φ47 mm × 8 mm cold rolled tube of heat resistant steel TP310HCbN（/%：0.07 C,0.39 Si,1.20 Mn,25.05 Cr,20.40 Ni,0.42 Nb,0.266N） solid-solution-treated at 1 120~1 160 ℃ then rupture test at 700 ℃ for 0~19 570 h are analyzed by the test method including SEM,TEM,energy spectrum analysis and hardness test.Results show that as the heat resistant steel TP310 HCbN rupture test with 95~220 MPa at 700 ℃ for 0~1 000 h,with increasing test time,the hardness HV value increases from 237 to 255,as that for more than 1 000 h,the hardness value is no change;with increasing test time,the intragranular precipitates in steel change from granular type to rod type,and there is a lot of wormlike NbCrN precipitates which interacts with dislocation;the extrapolated rupture strength of produced test heat resistant steel TP310 HCbN at 700 ℃ for 100 000 h is 63.65 MPa to meet the requirement of standard.