一种新型镍基变形高温合金“孪晶+γ’相”组织调控及高温力学性能研究  

“Twin+γ' phase” Microstructure Regulation for a Novel Ni-based Wrought Superalloy and High Temperature Mechanical Properties

作　　者：丁雨田[1,2] 王涛[1,2] 王兴茂 高钰璧 毕中南 杜金辉[3] 甘斌[3] Ding Yutian;Wang Tao;Wang Xingmao;Gao Yubi;Bi Zhongnan;Du Jinhui;Gan Bin(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;School of Material Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Beijing Key Laboratory of Advanced High Temperature Materials,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050 [2]兰州理工大学材料科学与工程学院,甘肃兰州730050 [3]钢铁研究总院高温合金新材料北京市重点实验室,北京100081

出　　处：《稀有金属材料与工程》2023年第7期2549-2558,共10页Rare Metal Materials and Engineering

基　　金：国家重点研发计划(2017YFA0700703)。

摘　　要：本研究采用形变热处理的方法在新型镍基变形高温合金中构筑了“孪晶+γ’相”复合结构,并结合EBSD和SEM表征技术探讨了孪晶与γ’相的演变规律。同时,研究了合金在760℃下的高温力学性能。结果表明,“孪晶+γ’相”复合结构可以有效改善合金的高温力学性能,且随着退火孪晶长度分数的增加,孪晶片层厚度增加,材料的高温强度呈降低的趋势;当轧制态合金(ε=68%)在1120℃退火15 min并进行双级时效处理(650℃/24 h/AC和760℃/16 h/AC)后,“孪晶+γ’相”复合结构中退火孪晶的长度分数为25.38%,γ’相的平均尺寸为32.21nm,此时,合金的屈服强度从固溶态的775 MPa提高到了1184 MPa,断后伸长率从3.18%提高到了18.96%。通过构筑“孪晶+γ’相”复合结构可以有效提高高温合金的高温力学性能,这为高温力学性能的提升提供了一种新策略。The “twin+γ' phase” composite structure was constructed in a novel Ni-based wrought superalloy by thermomechanical treatment,and the evolution of twin and γ' phases was investigated by EBSD and SEM.Meanwhile,the high temperature mechanical properties of the alloy at 760 ℃ were studied.The results show that the “twin+γ' phase” composite structure can effectively improve the high temperature mechanical properties of the alloy,and with the increase in the length fraction of the annealing twin,the thickness of the twin lamellar increases,and the high temperature strength of the material decreases.When the rolled alloy(ε=68%) is annealed at 1120 ℃ for 15 min and subjected to two-stage aging treatment(650 ℃/24 h/AC and 760 ℃/16 h/AC),the length fraction of twins in the “twin+γ' phase” composite structure is 25.38% and the average size of γ' phase is 32.21 nm,the yield strength of the alloy increases from 775 MPa(solid solution state) to 1184 MPa,and the elongation after fracture increases from 3.18% to 18.96%.“Twin+γ' phase” composite structure can effectively improve the high-temperature mechanical properties of the superalloy,which provides a novel strategy for improving the high-temperature mechanical properties of superalloys.

关 键 词：新型镍基变形高温合金 “孪晶+γ’相”复合结构 退火孪晶 高温力学性能 

分 类 号：TG132.33[一般工业技术—材料科学与工程]