Zr-4合金小试样高温疲劳行为研究  

LCF Behavior of Zr-4 Alloy at Elevated Temperature

作　　者：叶裕明[1] 蔡力勋[1] 李聪[2] 

机构地区：[1]西南交通大学应用力学与工程系 [2]中国核动力院核燃料与材料国家级重点实验室,成都610041

出　　处：《核动力工程》2006年第3期37-42,共6页Nuclear Power Engineering

基　　金：核燃料与材料国家重点实验室基金资助(51481020203ZS8501)

摘　　要：基于Zr-4合金漏斗薄片小试样,完成了室温和400℃高温下的等幅横向应变循环与应变疲劳试验。根据弹塑性有限元分析,建立了基于局部应变等效的应变换算方法,并结合实验结果,得到了估算Zr-4合金应变疲劳寿命的Manson-Coffin模型。结果表明:低应变幅下,Zr-4合金表现出循环软化特征;高应变幅下,Zr-4合金表现出循环强化特征。高温严重降低了低应变幅下Zr-4合金的疲劳寿命,随着应变幅增加,温度影响趋弱。分析表明,基于传统应变转换公式的M-C模型用于估算疲劳寿命偏于保守。A series of strain fatigue tests were carried out on small bugle-like slice-specimens of Zr-4 alloy at room temperature and 400℃. According to Elastic and Plastic Finite Element Analysis and assumption of local damage equivalence, a strain conversion equation was given to transform the transverse strain of the specimen to the axial strain. Based on the test results of the alloy and the strain conversion equation, fatigue life estimation equations of Zr-4alloy, or M-C （Manson-Coffin） models, were obtained. The results showed that, Zr-4 alloy had obvious cyclic hardening character during high amplitude strain at different temperatures, but showed reverse character during low amplitude strain. Elevated temperature lowered seriously the fatigue life of Zr-4 alloy, and as the increasing of amplitude strain, temperature effect impaired gradually. Analysis showed that the prediction life by using M-C model based on the traditional strain conversion equation was quite conservative when axial strain amplitude was less than 5000 micro-strain.

关 键 词：ZR-4合金 小试样 应变疲劳 有限元分析 寿命估算 

分 类 号：TB302.3[一般工业技术—材料科学与工程] O346.2[理学—固体力学]