An as-annealed sheet of pure zirconium with bimodal basal texture was rolled at room temperature and samples with different rolling reductions were obtained. EBSD technique was employed to analyze the microstructure and texture. The existence of non-uniform microstructure was observed during the rolling deformation. A portion of grains tended not to deform, while the rest were readily elongated along the RD direction, leading to a deformation band at a heavy strain. The presence of twinning wasn't observed, so slip became the dominated deformation mode. Dislocation slip leaded to the increase of misorientation angle between neighboring points and accumulative misorientation. However, the variation of misorientation resulted by slip was very little. So the number of low angle grain boundaries ( LAGB ) increased remarkably as deformation continued, but grain orientation didn't change significantly. The bimodal basal texture retained with concentrating to ND. The < 11 2-0 >//RD texture transformed to < 10 10 >//RD gradually with strain increasing.%本文通过对具有双峰织构的退火态纯锆板材进行室温轧制,得到不同变形量的样品.利用EBSD对其微观组织和织构进行了分析.结果表明,板材在轧制过程中会产生不均匀组织.一部分晶粒难变形,另一部分容易变形且沿RD方向被拉长,在变形量较大时形成变形带.并且轧制板材组织中没有发现孪晶,因此滑移为主要的变形方式.大量的位错滑移造成了晶粒内部取向差和累积取向差的变化,但是仅仅通过滑移改变的晶粒间取向差非常小,因此,在轧制过程中通过滑移产生的小角度晶界增加,但是其晶体取向变化很小.在轧制过程中板材的基面双峰织构类型并无较大改变,只是逐渐向ND方向集中.而〈11(2)0〉//RD织构逐渐转变为〈10(1)0〉//RD织构.
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