Fully-reversed cyclic deformation of a pure Zr(a thickness of 17 mm)was conducted at two different strain amplitudes(0.4%and 0.8%)to investigate the deformation and crack initiation behaviors based on slip trace analy...Fully-reversed cyclic deformation of a pure Zr(a thickness of 17 mm)was conducted at two different strain amplitudes(0.4%and 0.8%)to investigate the deformation and crack initiation behaviors based on slip trace analysis.It was found that prismaticaslip with a higher Schmid Factor(m>0.4)was the dominant deformation mode.The grains containing persistent slip bands(PSBs)tended to go towards[1210]pole and the Schmid Factor had a critical value of 0.4 above which prismatic and pyramidal slip were dominant.Fatigue cracks were mainly initiated at PSBs and grain boundaries(GBs).It showed that 61.1%of the cracks were PSB cracks under a strain amplitude of 0.4%,while it decreased to 53.5%at a strain amplitude of 0.8%.PSB cracks were mainly parallel to prismaticaslip with higher Schmid Factor while some cracks tended to be initiated at GBs with higher misorientation angles.The interaction of PSBs with GBs would result in strain transferring to the neighboring grain.Strain transfer was more likely to occur at the condition of the higher geometrical compatibility factor m,and lower residual Burgers vectorb,which could reduce strain localization.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52275161)International Joint Research Center for Value-added Metallurgy and Processing of Non-ferrous Metals(Grant No.2019SD0010)+1 种基金Qin Chuangyuan“Scientist+Engineer”Team Construction in Shaanxi Province(Grant No.2022KXJ-145)Innovation Talent Promotion Program-Science and Technology Innovation Team(Grant No.2023-CX-TD-50).
文摘Fully-reversed cyclic deformation of a pure Zr(a thickness of 17 mm)was conducted at two different strain amplitudes(0.4%and 0.8%)to investigate the deformation and crack initiation behaviors based on slip trace analysis.It was found that prismaticaslip with a higher Schmid Factor(m>0.4)was the dominant deformation mode.The grains containing persistent slip bands(PSBs)tended to go towards[1210]pole and the Schmid Factor had a critical value of 0.4 above which prismatic and pyramidal slip were dominant.Fatigue cracks were mainly initiated at PSBs and grain boundaries(GBs).It showed that 61.1%of the cracks were PSB cracks under a strain amplitude of 0.4%,while it decreased to 53.5%at a strain amplitude of 0.8%.PSB cracks were mainly parallel to prismaticaslip with higher Schmid Factor while some cracks tended to be initiated at GBs with higher misorientation angles.The interaction of PSBs with GBs would result in strain transferring to the neighboring grain.Strain transfer was more likely to occur at the condition of the higher geometrical compatibility factor m,and lower residual Burgers vectorb,which could reduce strain localization.
