摘要
研究了超细晶工业纯锆在0.875R_(p0.2)、0.9R_(p0.2)、0.9125R_(p0.2)、0.925R_(p0.2)、0.9375R_(p0.2)、0.95R_(p0.2)蠕变应力下的室温蠕变性能,计算了超细晶工业纯锆的稳态蠕变速率,并分析了其蠕变断裂机理。结果表明:超细晶工业纯锆在蠕变应力为0.875R_(p0.2)时,出现了蠕变饱和现象,稳态蠕变速率随着蠕变应力的增加而增大,稳态蠕变阶段缩短;室温下,工业纯锆经复合细化后蠕变抗性显著提高;当蠕变应力为0.95R_(p0.2)时,稳态蠕变速率达到最大值3.140×10^(-6) s^(-1)。通过计算蠕变应力指数,得到超细晶工业纯锆的室温蠕变机理为位错运动。超细晶工业纯锆室温蠕变断裂为韧性断裂。
Creep tests were carried out on ultra-fine grained commercial purity zirconium under the stresses of 0.875Rp0.2,0.9Rp0.2,0.9125Rp0.2,0.925Rp0.2,0.9375Rp0.2 and 0.95Rp0.2 at ambient temperature.Steady state creep rate was calculated.The creep fracture of the UFG CP Zr was investigated by SEM.A new expression was proposed which fitted the creep of UFG CP Zr better.It is found that the creep saturation phenomenon happens under the creep stress of 0.875Rp0.2;the steady state creep rate increases with the increase of creep stress and thus the steady state creep stage shortens;the creep resistance of UFG CP Zr is better than that of CG CP Zr at ambient temperature;the maximum of steady state creep rate is 3.140×10^-6 s^-1 under 0.95Rp0.2.According to the calculated creep stress exponent,the creep mechanism can be categorized into the dislocation motion.The creep fracture of UFG CP Zr is ductile fracture.
作者
杨西荣
朱振
刘晓燕
罗雷
赵西成
Yang Xirong;Zhu Zhen;Liu Xiaoyan;Luo Lei;Zhao Xicheng(Xi'an University of Architecture and Technology,Xi'an 710055,China;Metallurgical Engineering Technology Research Center of Shaanxi Province,Xi'an 710055,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2019年第3期815-819,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51474170)
陕西省自然科学基金(2016JQ5026)
陕西省教育厅重点实验室科研计划项目(15JS058)
