中文摘要：

为了给实际应用中国产M5、Zirlo合金的安全和寿命提供理论依据.文中通过对国产M5和Zirlo合金在高温高压水蒸气下进行1 000h的氧化试验,分析氧化动力学,结合扫描电镜和能谱分析仪观察试样氧化产物的微观形貌和成分变化,研究其在高温高压水蒸气环境下的氧化行为.在室温下对不同氧化时长的M5和Zirlo合金进行环向拉伸试验,分析其力学性能以及观察断口形貌.试验结果表明：M5和Zirlo合金氧化动力学方程分别为wM5=0.001t^0.766 1,R=0.935 15以及wZirlo=0.000 58t^0.399 3,R=0.808 34.Zirlo合金1 000h单位面积氧化增重为0.008 4mg·mm^-2,远小于M5合金0.21mg·mm^-2.M5合金随着氧化时长的增加试样表面被针状的氧化产物完全覆盖,Zirlo合金随着氧化时长增加针状氧化产物增加至1 000h未完全覆盖试样表面.M5合金表面O元素比例随氧化时长增加逐步增大,Zirlo合金表面O元素随着氧化时长增加变化不大.Zirlo合金抗氧化性能优于M5合金.M5在氧化1 000h内强度影响不大,Zirlo合金的强度随着时间的延长有所下降,M5和Zirlo合金的伸长率和断面收缩率随着氧化时间的延长均有所下降,Zirlo合金的伸长率和断面收缩率都小于M5合金,氧化后M5合金的塑性优于Zirlo合金.两者的拉伸断口均为微孔聚集型断裂,断裂类型为韧性断裂.M5合金的力学性能较Zirlo合金更稳定.

英文摘要：

In order to provide theoretical basis for the safety of domestic M5 and Zirlo alloy in practical application.The oxidation behavior of M5 and Zirlo alloy which were exposed to high-temperature and high-pressure steam was investigated.The oxidation test for domestic M5 and Zirlo alloy was carried out in high-temperature and high-pressure steam for 1000 hours,after which the micro-morphology and compositional change of the samples were observed by scanning electron microscopy（SEM）and energy dispersive spectrometer（EDS）.Besides,in order to analyze their mechanical properties and to observe their fracture morphology,the ring tensile test for M5 and Zirlo alloy with different oxidation time was carried out at room temperature.The experimental results showed that：the oxidation kinetics curves of M5 and Zirlo alloy follow the parabolic rate law（wM5=0.001t^0.766 1,R=0.935 15,wZirlo=0.000 58t^0.399 3,R=0.808 34）.The oxidation weight gain per unit area of the alloy Zirlo which is 0.008 4mg·mm^-2 is far less than that of the M5 which is 0.21mg·mm^-2 alloy.As for alloy M5,the homogeneous and dense oxidation products were produced on the sample surface with the increase of the oxidation time.The surface oxidation of the Zirlo alloy is inhomogeneous after 1 000hours＇ oxidation.In addition,the surface oxygen element ratio of the alloy M5 gradually increased with the increase of the oxidation time while the surface oxygen element ratio of the Zirlo alloy showed no obvious change with increasing the oxidation time.The oxidation resistance of the Zirlo alloy is superior to that of the alloy M5.What＇s more,the mechanical property of M5 kept almost constant within the oxidation time of 1 000 hours,but for Zirlo alloy,it decreased to some extent within the oxidation time of 1 000 hours.Also,both of their tensile fractures belong to the micro-void accumulation fracture and the fracture mode is characterized to be ductile fracture.In general,the mechanical property of alloy M5 is more stable than that of Zirlo alloy