title: A study on alkaline heat treated Mg-Ca alloy for the control of the biocorrosion rate.
abstract: To reduce the biocorrosion rate by surface modification, Mg-Ca alloy (1.4wt.% Ca content) was soaked in three alkaline solutions (Na(2)HPO(4), Na(2)CO(3) and NaHCO(3)) for 24h, respectively, and subsequently heat treated at 773K for 12h. Scanning electron microscopy and energy-dispersive spectroscopy results revealed that magnesium oxide layers with the thickness of about 13, 9 and 26microm were formed on the surfaces of Mg-Ca alloy after the above different alkaline heat treatments. Atomic force microscopy showed that the surfaces of Mg-Ca alloy samples became rough after three alkaline heat treatments. The in vitro corrosion tests in simulated body fluid indicated that the corrosion rates of Mg-Ca alloy were effectively decreased after alkaline heat treatments, with the following sequence: NaHCO(3) heated<Na(2)HPO(4) heated<Na(2)CO(3) heated. The cytotoxicity evaluation revealed that none of the alkaline heat treated Mg-Ca alloy samples induced toxicity to L-929 cells during 7days culture.
authors.affiliation: State Key Laboratory for Turbulence and Complex System and Department of Advanced Materials and Nanotechnology, College of Engineering, Peking University, Beijing 100871, China.
authors.forename: X N
authors.initials: XN
authors.lastname: Gu
authors.forename: W
authors.initials: W
authors.lastname: Zheng
authors.forename: Y
authors.initials: Y
authors.lastname: Cheng
authors.forename: Y F
authors.initials: YF
authors.lastname: Zheng
mesh_terms: D000468:Alkalies / Q000737:chemistry*; D000497:Alloys / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D001826:Body Fluids / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry*; D003343:Corrosion; D006358:Hot Temperature; D007700:Kinetics; D008274:Magnesium / Q000737:chemistry*; D008422:Materials Testing; D013499:Surface Properties
chemical_list: D000468:Alkalies; D000497:Alloys; D001672:Biocompatible Materials; D008274:Magnesium; D002118:Calcium