Wang Yan, Cao Hailong, Yang Senlin, Tian Yuxing, Zhang Yuchun, Zhang Qiujin
2025, 54(2): 30-33.
In this paper, 9.0%,13.0%,17.0% and 21.0% cold deformation of LD7-5 alloy extruded bars are obtained by extrusion and cold deformation. The microstructure and mechanical properties of LD7-5 alloy bars under different cold deformation are analyzed by means of scanning electron microscopy and mechanical property testing. The results show that with the increase of cold deformation, the number of recrystallized grains increases, and their size decreases and becomes equiaxed gradually. With the increase of cold deformation, the second phase in the alloy is broken more fully, the distribution is more uniform, and the number of grain boundaries is larger, the grain boundary area is larger, the strength and elongation are larger. Finally, the Hal-Petch formula describing the relationship between grain size and mechanical properties of LD7-5 extruded bars is established, which provides a certain basis for regulating the microstructure and properties of LD7-5 alloy extruded bars by applying cold deformation.