title: Microstructures, aging behaviour and mechanical properties in hydrogen and chloride media of backward extruded Mg-Y based biomaterials.
abstract: Microstructures, aging behaviour from room temperature to 300 °C and mechanical properties in different media of backward extruded (BE) Mg-Y based biomaterial have been investigated. The results reveal that BE-Mg-Y based alloy is mainly composed of polygon-shaped grains and fine precipitates. The results of aging response show that BE-Mg-Y based alloy exhibits remarkable age hardening behaviour when the aging temperature is 200 °C and higher. The high mechanical properties of aged BE-Mg-Y based alloy are mostly associated with fine microstructure, solid solution strengthening and the existence of homogeneous precipitates. The hydrogen embrittlement dependence on the aging time is confirmed in BE-Mg-Y based alloy. Additionally, the strength and elongation of BE-Mg-Y based alloy are significantly influenced by the ion concentration in media. These results offer some implications for understanding the reduced strength of Mg based implants in body environment. It is demonstrated that the temporary high mechanical strength in air of BE-Mg-Y based biomaterials is insufficient to evaluate the in vivo mechanical integrity.
authors.affiliation: State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, PR China. pengqiuming@gmail.com
authors.forename: Qiuming
authors.initials: Q
authors.lastname: Peng
authors.forename: Ning
authors.initials: N
authors.lastname: Ma
authors.forename: Daqing
authors.initials: D
authors.lastname: Fang
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Riping
authors.initials: R
authors.lastname: Liu
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Tian
mesh_terms: D000497:Alloys / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry*; D006244:Hardness; D006859:Hydrogen / Q000737:chemistry*; D007101:Immersion; D008274:Magnesium / Q000737:chemistry*; D008422:Materials Testing; D055595:Mechanical Phenomena; D012996:Solutions; D013696:Temperature; D013997:Time Factors; D015019:Yttrium / Q000737:chemistry*
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D002712:Chlorides; D012996:Solutions; D015019:Yttrium; D006859:Hydrogen; D008274:Magnesium