【作者】 于兴福； 田素贵； 杨景红； 徐永波； 胡壮麒；

【Author】 Yu Xingfu Tian sugui Yang Jinghong Xu Yongbo Hu Zhuangqi ( School of Materials Science and Engineering, Shenyang University ofTechnology, Shenyang, 110023 )( Shenyang National Laboratory for Materials, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang, 110016)

【机构】 沈阳工业大学材料科学与工程学院； 中国科学院金属研究所材料科学国家(联合)实验室；

【摘要】 通过测定蠕变曲线和稳态蠕变期间位错运动的内摩擦应力,及微观组织形貌观察,研究了单晶Ni基合金内应力的影响因素及合金的变形机制。结果表明:随元素Ta、W含量的增加,可较大幅度地提高合金的内摩擦应力;合金4蠕变后期的变形特征是<110>螺、刃超位错切入γ’相中;高体积分数、且粗大的筏状γ’相及γ基体中细小γ’相可有效阻碍位错的运动,提高合金蠕变抗力,是导致该合金具有较高持久寿命的主要原因。更多还原

【Abstract】 By means of the measurement of creep curve and internal friction stress of dislocation movementduring steady state creep stage, and observation of microstructure, an investigation has been made into the deformation mechanism and effect factors of the internal friction stress of single crystal nickel - base superalloys during steady state creep stage. Results show that the values of internal friction stress of superalloys may be enhanced with the increase of the elements Ta and W concentration. The < 110 > super - dislocations shearing into the γ’ phase are supposed to be the deformation mechanism of the superalloy 4 in the period of creep later. The fact that the coarsening γ’ rafted phase and the finer cubic γ’ phase are precipitated in the γ matrix phase may effectively block the movement of dislocations , and enhance the creep resistance of the alloy, this is a main reason for resulting in the al- loy possessing a longer rupture lifetimes.更多还原