热加工对NZ2锆合金在400℃过热水蒸气中吸氢行为的影响

Effects of Hot Rolling on Hydrogen Absorption Behavior of NZ2 Zirconium Alloy in 400 ℃ Super-heated Steam

通过研究在相同加工率的条件下,不同热轧温度对锆合金第二相粒子的影响,来选择最优的加工工艺。实验采用NZ2锆合金,参照NZ2合金工业规模铸锭板材的加工工艺参数,选取热轧温度分别为800、700、650、610℃制得厚1.4mm的板材样品,进行400℃,10.3MPa过热蒸气腐蚀,在不同时间取样测其氢含量。通过金相,扫描电镜及透射电镜观察合金中第二相的分布、种类。结果表明,选择合适的热轧温度可以得到均匀、细小,弥散分布的第二相,进而制备出具有更高耐腐蚀性能且吸氢量较少的锆合金。

Effects of different hot rolling temperatures on the second phase particles of zirconium alloy were investigated under the same working rate to determine the optimum processing technique.NZ2 plates of 1.4 mm thickness were prepared at different hot rolling temperatures of 800,700,650 and 610 ℃ according to the processing parameters of commercial-scale ingot sheets and then were corroded in super-heated steam at 400 ℃,10.3 MPa.Their hydrogen content was measured at various time.The distribution and variety of the second phase of the alloys were observed by OM,SEM and TEM.Results show that uniform,fine and diffusive second phase can be obtained by selecting proper hot rolling temperature and therefore zirconium alloy can be prepared with high corrosion resistance and low hydrogen absorbability.