锆合金准静态压缩变形行为研究

Study of the deformation behavior for Zirconium alloys during quasi-static compression

本文以热轧退火态锆合金板材为研究对象,选用两种压缩试验样品,其压缩方向分别平行于原板材的法向(ND样品)和原板材的横向(TD样品),利用Gleeble热模拟试验机和EBSD分析技术,对两种样品准静态压缩变形行为进行了研究。结果表明,热轧退火态锆合金板材的准静态力学性能具有明显的各向异性,TD样品的屈服强度和流变应力均低于ND样品。且TD样品在变形过程中产生了一定数量的{10 12}拉伸孪晶,使TD样品中的晶粒c轴均向TD方向发生了转动。通过对两个加载方向的柱面滑移的Schmid Factor(SF)进行计算发现,TD样品的柱面滑移的SF大于ND样品,说明当加载方向沿着TD方向时,柱面滑移更容易开启,使得TD样品的屈服强度低于ND样品。

Quasi-static compression behaviors of zirconium alloys at room temperature were studied by Electron Backscattering Diffraction（EBSD） analysis.Two kinds of samples,which were cut from a hot-rolled and annealed sheet,were compressed with the compression axis paralleled to normal direction（ND sample） and transverse direction（TD sample） of the sheet,respectively.The results showed that during quasi-static compression,the yield strength and flow stress of the TD sample were lower than those of ND sample.Certain amount of {1012} tensile twinning was observed in TD samples with 10% compression,which flipped the c-axis and tended to align it with the compression axis near the TD.Based on the calculation result,the TD sampe displayed the higher Schmid Factor for prismatic slip during compression.It was an indication that compared to ND sample,the prismatic slip for TD sample was more easily to start and it had lower yield strength.