新型奥氏体耐热不锈钢的高温持久性能

Creep-Rupture Properties of a New Austenitic Heat-Resistant Stainless Steel at Elevated Temperature

以0Cr21Ni11SiNRE为对象,研究了该种新型奥氏体耐热不锈钢高温持久性能,分析了持久强度σ与持久寿命τ及Larson-Miller参数P之间的关系,并以此为基础预测了该钢种在750～927℃,103h下的持久强度。结果表明,在本试验条件下,0Cr21Ni11SiNRE的蠕变机制大体相同,其持久强度σ与持久寿命τ的对数,L-M参数P呈线性关系,其中,σ与P之间关系可表示为σ=-20.66×10-3P+589.25(2.33×104<P<2.7×104);通过回归计算得到其蠕变激活能Q=548kJ/mol,激活体积分数V=940mm3/mol。

The creep-properties of a new austenitic heat-resistant stainless steel 0Cr21 NillSiNRE were investigated and the relationships between rupture strength （σ） and rupture life （τ）, Larson-Mitler parameter （P） were analyzed at elevated temperature. Furthermore, rupture strength for 10^3 h at 750-927 ℃ of this steel were predicted on this basis. The results show that on the experimental conditions, creep mechanisms are roughly equal; there exists a linear relationship between σ and τ and P respectively, which σ is expressed as σ= -20.66 × 10^-3 P＋589.25 （2.33 × 10^4 〈P〈2.7 × 10^4 ）. By the regression analysis method, creep activation energy （Q） and the activation volume （V） of the steel are about 548 kJ/mol and 940 mm^3/mol respectively.