3D Fe-Rich Phases Evolution and Its Effects on the Fracture Behavior of Al-7.0Si-1.2Fe Alloys by Mn Neutralization

• 作者: Dong-Fu Song Yu-Liang Zhao Zhi Wang Yi-Wang Jia Dao-Xi Li Ya-Nan Fu Da-Tong Zhang Wei-Wen Zhang
• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2022,（1）
• 所属期刊栏目: Special Issue: Application of Synchrotron Radiation in Materials Research
• 页码范围: 163-175
• 页数: 13页
• 语种: 英文

摘要

The evolution of the 3D Fe-rich phases of Al-7.0Si-1.2Fe alloys with different Mn contents was visualized and character-ized using synchrotron X-ray computed tomography,and the effect of Fe-rich phases with typical morphologies on the fracture behavior during tensile testing was analyzed.The results showed that the Fe-rich phase changed from platelet-like β-Al5FeSi into α-Al15(FeMn)3Si2 with various morphologies after the addition of Mn.The Mn addition not only significantly reduced the volume fraction,equivalent diameter and interconnectivity of the Fe-rich phase but also greatly increased the sphericity,surface thickness,and distribution of the mean curvature and surface thickness.Furthermore,the equivalent diameter of α-Al15(FeMn)3Si2 had an inverse exponential function relationship with its sphericity.The 3D morphology of α-Al15(FeMn)3Si2 can be summarized as massive and regular polyhedrons,hollow and regular polyhedrons,and multi-branched polyhedrons.The fraction of the different 3D morphologies in each alloy is related to the Mn content,where excess Mn increased the number and volume fraction of the large Fe-rich particles with a low sphericity.The ductility of each alloy was significantly improved by the addition of Mn but gradually decreased when the Mn/Fe ratio exceeded 1.2.The increase in large α-Al15(MnFe)3Si2 with a low sphericity was the main reason for the decreased ductility of alloys with a high Mn content.