退火工艺对Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge合金耐腐蚀性能的影响

Effect of Annealing Process on the Corrosion Resistance of Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge Alloy

摘要:

利用静态高压釜腐蚀实验和SEM、TEM/EDS分析方法，研究了β相水淬后不同退火工艺对Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge合金的显微组织及在400 ℃/10.3 MPa过热蒸汽中耐腐蚀性能的影响。结果表明：500℃退火处理的样品发生了部分再结晶，退火时间对第二相尺寸的影响不明显；580℃退火处理的样品发生了完全再结晶，并且随着退火时间的延长，第二相的尺寸增大；合金元素主要以密排六方的Zr(Nb,Fe,Cr)2、四方的Zr3Ge和正交的Zr3Fe第二相析出；Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge合金在400 ℃/10.3MPa过热蒸汽中的耐腐蚀性能随着退火温度的升高和退火时间的延长而提高。

Abstract:

The corrosion resistance of Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge alloy samples with different annealing processes has been studied in super-heated steam at 400 ℃/10.3 MPa by autoclave test. The microstructure of the samples was investigated by TEM/EDS and SEM. The results show that partial recrystallization occurs in the samples annealed at 500 ℃, and the effect of annealing time on the size of second phase particles(SPPs) is not obvious; while complete recrystallization occurs in the samples annealed at 580 ℃, as the prolongation of annealing time, the size of SPPs enlarged in Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge alloy. There exist Zr(Nb,Fe,Cr)2 SPPs with a hexagonal close packed structure, tetragonal Zr3Ge and orthogonal Zr3Fe SPPs. The corrosion resistance of Zr-0.8Sn-0.25Nb-0.35Fe-0.1Cr-0.05Ge alloy in super-heated steam at 400 ℃/10.3 MPa is improved with the prolongation of annealing time and increase of annealing temperature.