热处理对N36锆合金腐蚀与吸氢性能的影响

将N36锆合金样品分别进行1 020 ℃/20 min WQ+C.R.+580 ℃/50 h AC、820 ℃/2 h AC+580 ℃/50 h AC、820 ℃/2 h AC+C.R.+580 ℃/50 h AC、700 ℃/4 h AC+C.R.+580 ℃/50 h AC 4种不同的热处理.用透射电镜观察了它们的显微组织，用高压釜腐蚀试验研究了它们在400 ℃/10.3 MPa过热水蒸气中的腐蚀与吸氢行为.结果表明：经1 020 ℃/20 min WQ+C.R.+580 ℃/50 h AC处理后样品的耐腐蚀性能最好，其原因在于合金中第二相细小弥散分布在晶界及晶内；而经820 ℃/2 h AC+580 ℃/50 h AC处理后样品的耐腐蚀性能最差，第二相主要集中在晶界上，且比较粗大.经820 ℃/2 h AC+C.R.+580 ℃/50 h AC、700 ℃/4 h AC+C.R.+580 ℃/50 h AC处理的样品的腐蚀性能介于两者之间.热处理对N36锆合金腐蚀时的吸氢行为有一定的影响，但不如对Zr 4合金的影响大，这可能是因为N36锆合金中的第二相吸氢能力不如Zr 4合金中的Zr(Fe,Cr)2第二相强的缘故.

Effect of Heat Treatments on Corrosion and Hydrogen Uptake Behaviors in N36 Zirconium Alloy

N36 zirconium alloy specimens were treated in different ways at 1 020 °C/20 min WQ + C.R. (cold rolling) + 580 °C/50 h AC， 820 °C/2 h AC+580 °C/50 h AC, 820 °C/2 h AC+C.R.+580 °C/50 h AC, and 700 °C/4 h AC+C.R.+580 °C/50 h AC, respectively. Their microstructures were examined by transmission electron microscopy (TEM). The corrosion and hydrogen uptake behaviors of these specimens were investigated after autoclave tests in superheated steam at 400 °C/10.3 MPa. Results show that the corrosion resistance of the specimen treated at 1 020 °C/20 min WQ+C.R. (cold rolling)+580 °C/50 h AC is the best among them. The reason is that such treatment makes the second phase particles fine and dispersed in α Zr matrix. The corrosion resistance of the specimen treated at 820 °C/2 h AC+580 °C/50 h AC was the worst due to the presence of coarse second phase particles. The corrosion resistance of these specimens treated at 820 °C/2 h AC+C.R.+580 °C/50 h AC and 〖JP2〗700 °C/4 h AC+C.R.+580 °C/50 h AC is in between. Heat treatments have less influence on hydrogen uptake of N36 than that of Zr 4. This may be the reason that the second phase particles in N36 alloy is less reactive with hydrogen than that of Zr(Fe,Cr)2 SPPs in Zr4.