β 相水淬对Zr-4合金在LiOH水溶液中耐腐蚀性能的影响
摘要
To investigate the effect ofβ-quenching on the corrosion behavior,Zr-4 specimens wereβ-quenched and subsequently annealed at 480—600℃for 2—200 h.The corrosion tests were carried out in 0.01 mol/L LiOH aqueous solution at 360β/18.6 MPa.The microstructure of Zr-4 specimens and fracture surface morphology of oxide films on the corroded specimens were observed by TEM and HRSEM,respectively.The results show that Zr-4 specimens exhibit excellent corrosion resistance as Zr-Sn-Nb alloys in LiOH aqueous solution after increasing the solid solution content of Fe and Cr inα-Zr matrix by suitable quenching rate fromβ-phase to avoid the formation ofβ-Zr. When the cooling rate is too fast,the specimens show worse corrosion resistance due to the formation ofβ-Zr.After annealing at 480—600℃,the better corrosion resistance of Zr-4 specimens can be obtained with increasing annealing temperture and time due to the decomposition ofβ-Zr.