Zhang Yunfei, Zhang Zhen, Sun Zhiyan, Zhao Yingli, Cui Yi, Zhang Zhongwu
School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China.
HBIS Group, HBIS Materials Technology Research Institute, Shijiazhuang 050023, China.
Nanomaterials (Basel). 2024 Dec 4;14(23):1949. doi: 10.3390/nano14231949.
The combination of cold deformation and solution aging is an important technological route for the bar processing of superalloy fasteners. The microstructure evolution and mechanical properties are intimately related to the process parameters. In this study, we systematically elucidate the mechanical properties and microstructure evolution of Fe-15Cr-25Ni alloys in different treatment processes and conduct in-depth analysis of the synergistic strengthening mechanism of fine-crystal strengthening, second-phase strengthening, and work hardening on Fe-15Cr-25Ni alloys. The results show that the tensile strength and yield strength at room temperature increase with the increase in grain refinement and dislocation density but decrease with the increase in elongation. After solid-solution treatment, most of the precipitates dissolve into the matrix, and the dislocation density is greatly reduced, resulting in a decrease in strength and an increase in plasticity. After aging, a large amount of γ' phase was precipitated. Due to the two strengthening effects of dislocation strengthening and second-phase strengthening, the strength of the aging state is more improved than that of the cold-drawing state. The purpose of this study is to provide valuable insights for the industrial production of Fe-15Cr-25Ni superalloys.
冷变形与固溶时效相结合是高温合金紧固件棒材加工的重要工艺路线。微观组织演变与力学性能密切相关于工艺参数。在本研究中，我们系统地阐明了Fe-15Cr-25Ni合金在不同处理工艺下的力学性能和微观组织演变，并对Fe-15Cr-25Ni合金的细晶强化、第二相强化和加工硬化的协同强化机制进行了深入分析。结果表明，室温下的抗拉强度和屈服强度随晶粒细化和位错密度的增加而增加，但随伸长率的增加而降低。固溶处理后，大部分析出相溶解到基体中，位错密度大大降低，导致强度降低，塑性增加。时效后，大量γ'相析出。由于位错强化和第二相强化的两种强化作用，时效态的强度比冷拉态有更大提高。本研究的目的是为Fe-15Cr-25Ni高温合金的工业生产提供有价值的见解。
