Fabrication of high strength and plasticity of Zn-Mg composites with core–shell structure by spark plasma sintering

• Published in: Materials letters Vol. 279; p. 128525
• Main Authors: Cui, Zeqin, Luo, Mengda, Zhang, Yakai, Gong, Dianqing, Wang, Wenxian, Wang, Jianzhong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.11.2020; Elsevier BV
• Subjects: Biomaterials; Compressive strength; Core-shell structure; Functional; Magnesium base alloys; Materials science; Mechanical properties; Medical materials; Microstructure; Plasma sintering; Plastic properties; Powder technology; Shells; Solid solutions; Spark plasma sintering; Surgical implants; Synergistic effect; Zinc base alloys; Functional; Powder technology; Microstructure; Biomaterials
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.128525

•Zn-Mg composites with core–shell structure were produced by spark plasma sintering.•The core–shell unit was composed of isolated soft Mg core and hard MgZn2 shell.•General mechanisms of strengthening mechanical properties are suggested.•Medium compressive strength predetermine these materials for bone implants. To make zinc alloy as a degradable medical material with better comprehensive mechanical properties, Zn-Mg composite with isolated core–shell (I-CS) or three-dimensional core–shell (3D-CS) structures was produced by spark plasma sintering (SPS). The microstructure showed that the core–shell structure was composed of isolated soft Mg core and continuous solid solution hard MgZn2 shell. The mechanical properties indicated that the compressive strength (~234 MPa) of Zn-Mg alloy with 3D-CS structure was greatly improved, while maintaining the moderate ductility (fracture plasticity of ~8%), which fully meets the performance requirements of implants. This core–shell structure provides a novel material design approach and improves the synergistic effect of material strength and plasticity.