铸造镍基合金K44的高温蠕变行为  

HIGH TEMPERATURE CREEP BEHAVIOR OF CAST Ni BASE SUPERALLOY K44

作　　者：侯介山[1] 张玉龙[2] 郭建亭[1] 冀光[2] 周兰章[1] 叶恒强[1] 

机构地区：[1]中国科学院金属研究所,沈阳110016 [2]中国人民解放军驻哈尔滨汽轮机厂有限责任公司军事代表室,哈尔滨150046

出　　处：《金属学报》2004年第6期579-584,共6页Acta Metallurgica Sinica

摘　　要：研究了铸造镍基高温合金K44在850—900℃,225—380MPa的高温拉伸蠕变行为.结果表明,实验合金蠕变曲线具有较短的初始阶段和较长的加速阶段,加速阶段较长是由于筏形化的γ′粒子和位错相互作用促成的.加速蠕变为应变软化阶段时,可以由关系式ε=ε_(min)(1+c′Δε)exp(n′Δε)来描述.蠕变断裂数据遵守Monkman-Grant规律,裂纹起源于晶界或枝晶界的空洞.High temperature tensile creep behaviors of cast nickel-based superalloy K44 in the temperature range of 850-900degreesC and under the applied stress range of 225-380 MPa have been studied. The results indicate that all of the creep curves of test alloys have similar shape: a short primary creep and a dominant accelerated creep stage, and the long accelerated stage is due to the interaction between rafting gamma' particles and dislocations. As the creep strain is a softening stage, the accelerated creep can be approximately described by expression (epsilon) overdot = (epsilon) overdot(min)(1 + c'Deltaepsilon)exp(n'Deltaepsilon). The creep fracture data follow the Monkman-Grant relationship. Cracks originate from the cavities at grain boundary or interdendritic.

关 键 词：镍基高温合金 高温蠕变 蠕变断裂 

分 类 号：TG111.8[金属学及工艺—物理冶金] TG146.1[金属学及工艺—金属学]