Texture Evolution and Ultrafine Grain Formation in Cross-Cryo-Rolled Zircaloy-2  

作　　者：Sunkulp Goel R.Jayaganthan I.V.Singh D.Srivastava G.K.Dey N.Saibaba 

机构地区：[1]Department of Metallurgical and Materials Engineering,Centre of Nanotechnology [2]Department of Mechanical and Industrial Engineering [3]Materials Science Division,Bhabha Atomic Research Center [4]Nuclear Fuel Complex Limited

出　　处：《Acta Metallurgica Sinica(English Letters)》2015年第7期837-846,共10页金属学报（英文版）

基　　金：BRNS,Bombay for their financial grant to this work (No.BRN-577-MMD)

摘　　要：The texture and mechanical properties of cross-rolled zircaloy-2 at 77 and 300 K were investigated.Crossrolling at 77 K was performed to impart different thickness reductions of 25% and 50%,while at 300 K with 25%,50%,75% and 85% reductions to the sample.EBSD analysis of deformed sample showed that near-basal orientation is not deformed completely after 50% rolling reduction.The activation of prismatic silp,{1122} contraction twin and {1012} extension twin were evident from the deformed microstructure at 77 K.The propensity for activation of basal slip〈a〉 at77 K was also observed.The deformation of the sample at 300 K occurs by prismatic,basal 〈a〉 and pyramidal 〈c＋a〉slips,which were predicted by pole figures.After annealing,the tensile strengths（735 and 710 MPa） are almost the same for 50% cryo-cross-rolled and room-temperature cross-rolled zircaloy-2 with almost 2.7% difference in their ductility.KAM analysis of the deformed samples was made to estimate the stored strain energy and dislocation density.Annealing of deformed sample at 673 K for 30 min results in recrystallization,which leads to the formation of ultrafine grains.The texture and mechanical properties of cross-rolled zircaloy-2 at 77 and 300 K were investigated.Crossrolling at 77 K was performed to impart different thickness reductions of 25% and 50%,while at 300 K with 25%,50%,75% and 85% reductions to the sample.EBSD analysis of deformed sample showed that near-basal orientation is not deformed completely after 50% rolling reduction.The activation of prismatic silp,{1122} contraction twin and {1012} extension twin were evident from the deformed microstructure at 77 K.The propensity for activation of basal slip〈a〉 at77 K was also observed.The deformation of the sample at 300 K occurs by prismatic,basal 〈a〉 and pyramidal 〈c＋a〉slips,which were predicted by pole figures.After annealing,the tensile strengths（735 and 710 MPa） are almost the same for 50% cryo-cross-rolled and room-temperature cross-rolled zircaloy-2 with almost 2.7% difference in their ductility.KAM analysis of the deformed samples was made to estimate the stored strain energy and dislocation density.Annealing of deformed sample at 673 K for 30 min results in recrystallization,which leads to the formation of ultrafine grains.

关 键 词：Cross-rolling EBSD TEM Ultrafine grains Texture 

分 类 号：TG339[金属学及工艺—金属压力加工]