Microstructural Improvement of Eutectic Al + Mg2Si Phases on Al–Zn–Si–Mg Cast Alloy with TiB2 Particles Additions

• Published in: Materials Vol. 14; no. 11; p. 2902
• Main Authors: Kim, Byungjoo, Hwang, Jihoon, Park, Yongho, Lee, Youngcheol
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 28-05-2021; MDPI
• Subjects: Alloys; aluminum alloy; Aluminum base alloys; Casting alloys; Crystal structure; eutectic Al + Mg2Si phases; Eutectics; Grain size; intermetallic compound; Intermetallic compounds; Magnesium compounds; Mechanical properties; Metal silicides; Nucleation; phase modification; Phases; Silicon; Stress concentration; Titanium diboride; Zinc; United States > US
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14112902

In this study, the effects of adding TiB2 particles to eutectic Al + Mg2Si phases in aluminum alloys were analyzed. The eutectic Al + Mg2Si phases were modified effectively when a large amount of TiB2 was added, and changes in the shape, size, and distribution of the eutectic Al + Mg2Si phases were confirmed using a polarizing microscope and FE-SEM. The crystal structure of the TiB2 particles and Mg2Si phases were analyzed using HR-TEM, and the analysis confirmed that the TiB2 particles can act as heterogeneous nucleation sites. This paper intends to clarify the principle of phase modification of the eutectic Al + Mg2Si phases by TiB2 particles and proposes a new mechanism to improve Mg2Si phase modification when TiB2 particles are added.