In this study, a novel Sr-based bulk metallic glass (BMG) with nominal composition of Sr40 Mg20 Zn15 Yb20 Cu5 (at.%) was fabricated with high-purity raw materials by induction-melting method. Its mechanical properties, corrosion behavior, and cellular compatibility were studied in vitro as a feasibility evaluation of potential biodegradable metal. The compression strength of Sr40 Mg20 Zn15 Yb20 Cu5 alloy was (408.2 ± 20.0) MPa, which was much higher than human bone (164-240 MPa). Its Young's modulus (20.6 ± 0.2) GPa was quite close to human bone (5-23 GPa). MTT assay and PNPP method were employed to measure the proliferation ability and ALP activity of the experimental Sr-based BMG. The results 0-1 grade cytotoxicity and high ALP activity revealed that it was harmless to osteoblast-like MG63 cells. Additionally, the cells cultured on the surface of Sr40 Mg20 Zn15 Yb20 Cu5 alloy plate exhibited polygonal and dorsal ruffle configuration, and were well attached to the substrate by cellular extension, indicating their healthy status. The combination of increased mechanical strength, greater corrosion resistance, and excellent biocompatibility makes the Sr40 Mg20 Zn15 Yb20 Cu5 BMG very attractive material for biodegradable orthopedic implant applications.

A combined first principle and experimental study of the microstructural characteristics of oxide scales developed on type 430 stainless steel during hot rolling is presented. The oxide layer structures have been investigated by means of SEM, XPS and GDS. The oxide scales were found to have a multilayer structure with Si enrichment at the oxide/matrix interface and were identified as (Fe,Cr) 2 O 3 /(Fe,Cr) 3 O 4 /Cr 2 O 3 , FeO and Si rich region/Fe-Cr stainless steel from the outer to the inner layer. An atomistic model of the Fe-Cr/FeO interface has been generated through first principle methods based on density functional theory. Structural and electronic properties are compared to available experimental data and studied as they evolve across the Fe-Cr/FeO and Fe-Cr (Si)/FeO interface.