氢化物对N18锆合金原位拉伸变形的影响

Effects of hydrides on in situ tension elongation of N18 zirconium alloy

摘要:

采用扫描电镜下原位拉伸方法，观察研究了电解渗氢后的N18锆合金中氢化物的变形过程和基体的滑移行为，分析了氢化物对拉伸性能的影响。研究发现，锆合金基体的塑性变形是由多滑移引起的，氢化物可随基体发生较大变形。稀疏分布的带状氢化物簇对滑移的阻碍小，滑移线能够穿过而不改变方向，但尺寸较大的氢化物簇会阻碍滑移带的穿过而改变滑移方向。氢化物使抗拉强度略有增加，伸长率显著下降，但氢含量达到623ppm的N18锆合金的伸长率仍然达到了13.1%，具有较好的塑性。

Abstract:

By in situ tension observed with SEM, the deformation of hydrides and the slip behavior were investigated for the N18 zircaloy, which had been charged hydrogen by electrolytic hydrogenation method. And the effects of hydrides on the tensile properties were discussed. The results show that, the deformation of zircaloy results from multiple slip and the hydrides can be deformed evidently with matrix. The sparse strip clusters are not able to block the slip band movement, even to change the slip direction. But the big and thick strip clusters can stop the slip movement, or change the direction. The hydrides can increase the tensile strength slightly and decrease the elongation greatly. But the N18 zircaloy with 623 ppm hydrogen still has 13.1% elongation, an acceptable ductility.