11.5CrNbTi和15Cr0.5MoNbTi超纯铁素体不锈钢的循环蠕变行为  

Cyclic Creep Behavior of 11.5CrNbTi and 15Cr0.5MoNbTi Ultra Pure Ferritic Stainless Steels

作　　者：应彩虹[1,2] 陈立佳[1] 刘天龙[1] 郭连权[2] YING Caihong CHEN Lijia LIU Tianlong GUO Lianquan(School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China School of Science, Shenyang University of Technology, Shenyang 110870, China)

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870 [2]沈阳工业大学理学院,沈阳110870

出　　处：《材料研究学报》2017年第7期481-488,共8页Chinese Journal of Materials Research

基　　金：国家自然科学基金(51134010)~~

摘　　要：对11.5CrNbTi和15Cr0.5MoNbTi超纯铁素体不锈钢进行650℃应力控制循环蠕变实验,研究了最大外加应力处引入的保持时间对铁素体不锈钢的循环蠕变变形和断裂行为的影响。结果表明:保持时间的延长使这两种不锈钢的最小循环蠕变速率增大,循环蠕变寿命和循环断裂周次减少。在相同的条件下,15Cr0.5MoNbTi不锈钢的循环蠕变抗力优于11.5CrNbTi不锈钢。这两种不锈钢的循环蠕变断裂模式均为穿晶断裂,随着保持时间的延长断口表面的蠕变孔洞增多,蠕变损伤作用增强。这两种不锈钢循环蠕变后的微观组织均为亚晶,位错的滑移和交滑移是循环蠕变的主要变形机制。Cyclic creep tests at 650°C for both 11.5CrNbTi and 15Cr0.5MoNbTi ultra pure ferritic stainless steels were conducted under the stress-controlled mode, the effect of hold time introduced at the maximum applied stress on the deformation and fracture behaviors of the ferritic stainless steels was investigated. The results show that with prolonging the hold time, the minimum cyclic creep rate increases,and the cyclic creep life and the cycle number to fracture decrease for both stainless steels. Under the same conditions, the cyclic creep resistance of the 15Cr0.5MoNbTi stainless steel is higher than that of the 11.5CrNbTi stainless steel. The cyclic creep fracture mode for two stainless steels is transgranular fracture. With prolonging the hold time, the quantity of creep voids increases and the effect of creep damage gets enhanced. The microstructures after the cyclic creep are composed of sub-grains. The deformation mechanism of cyclic creep is mainly the dislocation slip and cross slip.

关 键 词：金属材料 超纯铁素体不锈钢 循环蠕变 保持时间 断裂模式 变形机制 

分 类 号：TG142[一般工业技术—材料科学与工程]