钴含量对电沉积纳米晶镍钴合金组织与力学性能的 - 中国有色金属学报.pdf

文章编号：1004-0609(2010)01-0092-08 钴含量对电沉积纳米晶镍钴合金组织与力学性能的影响 1 1, 2 1 许伟长 ，戴品强 ，郑耀东 (1. 福州大学 材料科学与工程学院，福州 350108 ； 2. 福建工程学院 材料科学与工程系，福州 350108) 摘 要：采用脉冲电沉积技术制备钴含量在 2.4%~59.3%范围内的镍钴合金。利用 XRD 与 TEM 技术对纳米晶镍 钴合金的组织结构进行表征。结果表明：所有成分的纳米晶镍钴合金均为面心立方结构的单相固溶体，平均晶粒 尺寸为 11~24 nm，且平均晶粒尺寸随钴含量的增加而减小，镍钴合金镀态下TEM 组织中观察到的晶粒尺寸与XRD 测量结果一致；纳米晶镍钴合金抗拉强度为 1 300~1 650 MPa，断裂伸长率为 10.5%~14.5%，镍钴合金的抗拉强 度与断裂伸长率均随钴含量的增加而提高；随着钴含量的不断增加，镍钴合金在单向拉伸过程中的应力诱发晶粒 长大被逐渐抑制，提高加工硬化率，塑性失稳被延迟，从而提高塑性。 关键词：镍钴合金；纳米晶；力学性能；晶粒长大；变形机制 中图分类号：TG 174.441 文献标识码：A Effect of Co content on structures and mechanical properties of electrodeposited nanocrystalline Ni-Co alloys 1 1, 2 1 XU Wei-chang , DAI Pin-qiang , ZHENG Yao-dong (1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, China; 2. Department of Materials Science and Engineering, College of Fujian Engineering, Fuzhou 350108, China) Abstract: Ni-Co alloys with Co content varying from 2.4% to 59.3% were prepared by pulse electrodeposition nanocrystalline. The microstructures of the nanocrystalline Ni-Co alloys were characterized by XRD and TEM. The analysis of XRD indicates that nanocrystalline Ni-Co alloys are all face-centered cubic structure, single-phase solid solution with an average grain size in the range of 11−24 nm, and the average grain size decreases with increasing Co content. The grain size observed in the TEM structures of as-deposited Ni-Co alloys is consistent with that measured by XRD. For