织构对Zr-4合金循环变形行为的影响  

Effect of Texture on Cyclic-deformation Behavior of Zircaloy-4

作　　者：李聪[1] 谭军[1] 应诗浩[1] 沈保罗[2] 邱绍宇[1] 

机构地区：[1]中国核动力研究设计院核燃料及材料国家级重点实验室,成都610041 [2]四川大学材料科学与工程学院,成都610065

出　　处：《核动力工程》2004年第2期137-141,167,共6页Nuclear Power Engineering

基　　金：国防科技重点实验室基金资助项目(51481020203ZS8501);四川省杰出青年学科带头人培养基金资助项目(03ZQ026-051);中国核 动力研究设计院青年基金资助项目(02-0-4-02)

摘　　要：研究了织构对Zr-4合金循环变形行为的影响及其作用机制。结果表明,(1)合金的低周疲劳寿命遵循Coffin-Manson关系NfβpeD=C。在给定peD时,轧向的寿命比横向的长。随peD的降低,两个方向的疲劳寿命差别增大;(2)在低应变幅,合金表现为循环软化直至疲劳破坏。在高应变幅,循环变形的初期表现为循环硬化,随后是循环软化直至疲劳破坏。在应变幅恒定时,随着循环次数的增加,晶粒发生转动,使晶粒有更高的Schmid因子;(3)半寿命时的ss随pe的变化遵循乘幂关系ss=snpsKe,ibs随pe的变化则遵循对数关系s=bKeln+C;(4)轧向和横向之间循环变形行为的差别是由于织构效应的缘故。The effect of texture on cyclic-deformation behavior of Zircaloy-4 is investigated. The results indicate that (1) the alloy obeys the Coffin-Manson relation (NfβΔΕp=C), the low-cycle fatigue life in the rolling direction is higher than that in the transverse direction at a given Εp, and the life difference between both directions becomes larger with lowering the Εp; (2) the alloy shows cyclic-deformation softening till fracture under low strain amplitude, showing cyclic-deformation hardening in the early stage and then cyclic-deformation softening till fracture under high strain amplitude, and the grains would rotate with the cyclic-deformation going on at a given amplitude where these grains have higher Schmid factor; (3) σs at half-life obeys the power law relation σs = KsΕpns, and σib obeys the logarithmic relation σib=KblnΕp+Cb; (4) the cyclic-deformation behavior difference in both directions stems from the texture effect. Finally, the mechanism on texture effect is discussed in detail.

关 键 词：ZR-4合金 循环变形 低周疲劳 织构 

分 类 号：TG113.255[金属学及工艺—物理冶金]