热处理对Fe-Ni合金丝力学性能和膨胀特性的影响  

Influence of heat treatments on the tensile properties and thermal expansion behavior of Fe-Ni wire

作　　者：陈保安 张强 王瑞红[3] 韩钰 丁一 祝志祥 陈新 杨长龙[4] 张宏宇 CHEN Bao-an;ZHANG Qiang;WANG Rui-hong;HAN Yu;DING Yi;ZHU Zhi-xiang;CHEN Xin;YANG Chang-long;ZHANG Hong-yu(State Key Laboratory of Advanced Power Transmission Technology,Global Energy Interconnection Research Institute Co.,Ltd.,Beijing 102209,China;Department of Electrical Engineering New Materials,Global Energy Interconnection Research Institute Co.,Ltd.,Beijing 102209,China;School of Materials Science and Engineering,Xi＇an University of Technology,Xi＇an 710048,China;Shenyang Electric Power Supply Company,State Grid Liaoning Electric Power Supply Co.,Ltd.,Shenyang 110003,China)

机构地区：[1]全球能源互联网研究院有限公司先进输电技术国家重点实验室,北京102209 [2]全球能源互联网研究院有限公司电工新材料研究所,北京102209 [3]西安理工大学材料科学与工程学院,西安710048 [4]国网辽宁省电力有限公司沈阳供电公司,沈阳110003

出　　处：《工程科学学报》2018年第11期1351-1357,共7页Chinese Journal of Engineering

摘　　要：分别采用X射线衍射、金相显微镜、原子力显微镜和透射电镜等组织表征手段以及室温拉伸和热膨胀系数测试等性能测试方法,对比研究了高温退火、低温时效处理对冷拔Fe-Ni合金丝微观组织演变、拉伸强度以及热膨胀系数的影响.研究结果表明：原始丝材强度高,但是室温热膨胀系数较大;而950℃退火导致晶粒粗化以及位错密度降低,虽然室温热膨胀系数低,但强度不足.相比之下,500℃较低温度的时效处理,能获得最优的强度/热膨胀系数组合（1189 MPa/0. 2×10^（-6）℃^（-1））.对Fe-Ni合金丝相应的强化机制以及热膨胀系数的影响因素分别进行了讨论分析,分析结果表明：细晶强化与位错强化是该合金丝的主要强化机制,而热膨胀系数则主要受溶质原子-位错交互作用影响.揭示出,合适的热处理工艺选择对于Fe-Ni合金丝力学性能/热膨胀性能优化具有重要意义.Although Fe-Ni wires have numerous potential applications,the effect of heat treatments on the microstructures and properties of Fe-Ni wires is currently unclear. In this study,different high-temperature annealing and low-temperature aging treatments（ i. e.,（1） annealing at 950 ℃ for 3 h ＋ quenching,（2） annealing at 950 ℃ for 3 h ＋ quenching ＋ aging at 500 ℃ for 2 h,and（3） aging at 500 ℃ for 2 h） were applied to cold-drawn Fe-36. 24% Ni alloy wires to comparatively investigate their influences on the microstructural evolution,tensile strength,and thermal expansion coefficient,with the aid of microstructural characterization methods,such as X-ray diffraction,optical microscopy,atomic force microscopy,and transmission electron microscopy,as well as property measure-ments,such as room-temperature tensile testing and thermal expansion coefficient. The experimental results clearly show that the as-drawnFe-Ni wire,although having a high tensile strength,exhibits an unfavorable high thermal expansion coefficient. The Fe-Ni wires annealed at 950 ℃（ wires subjected to（1） and（2）） have a relatively low thermal expansion coefficient but exhibit insufficient strength. In comparison,the wire aged at 500 ℃（ wire subjected to（3）） shows a high strength（ 1189 MPa） and a low thermal expansion coefficient（ 0. 2 × 10^（-6）℃^（-1）） at the same time. The relative strengthening mechanisms and factors affecting the thermal expansion coefficient are discussed and analyzed in terms of the microstructures. Grain boundary strengthening and dislocation hardening are observed to be the dominant strengthening mechanisms of the Fe-Ni wires,and the solute atom-dislocation interaction is mainly responsible for the evolution of the thermal expansion coefficient. The present work clearly demonstrates that suitable heat treatments are important for the optimization of the strength/thermal expansion coefficient of Fe-Ni alloy wires,which will be helpful for material design and tech

关 键 词：FE-NI合金 热处理 强度 热膨胀系数 

分 类 号：TG142.1[一般工业技术—材料科学与工程]