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X-ray fluorescence provides a powerful means of non-destructively determining the elemental composition of a sample. X-rays from a Molybdenum (Mo) source was fired on copper, molybdenum, lead, steel and brass samples to determine their composition and relative abundance of their constituent elements. Two different detectors : the Cadmium Telluride (CdTe) and Silicon(Si) detectors were used to pick up the signals from the scattering of the X-rays at the sample surfaces and their energy resolutions as well as efficiencies were compared. With a non-noisy amplifier, the Si detector had a higher resolution (0.27 % ) when compared to the 0.38 % for the CdTe detector but it had a lower efficiency when compared to that of the CdTe detector. It was also discovered that higher energies produced lower detector efficiencies. [ABSTRACT FROM AUTHOR]

Effects of solution treatment (T4), solution and ageing treatment (T6) on the degradation behaviours, mechanical properties and cytocompatibility of the extruded Mg-1.5Zn-0.5Y-0.5Zr alloy were studied in this work. Microstructural characterisation including SEM and TEM observation, degradation behaviours, tensile experiment and cytocompatibility tests was carried out. It showed that the alloy after 500°C × 2 h and 12 h ageing treatment exhibited the best degradation resistance with the degradation rate of 0.11 ± 0.01 mm/y in Hank's solution. Moreover, the fine and uniform distributed second phases after 12 h ageing treatment could effectively improve the ultimate tensile strength (UTS) of the alloy. Due to the low degradation rate, the alloy after 500°C solution and 12 h ageing treatment also exhibited good cytocompatibility with cell viability value of more than 90%. In essence, 500°C × 2 h and 12 h ageing was the best heat treatment practice for Mg-1.5Zn-0.5Y-0.5Zr alloy. [ABSTRACT FROM AUTHOR]

The influence of external magnetic and Aharonov‐Bohm (AB) flux fields on the energy spectra and thermal properties of N2, NO, CO and H2 diatomic molecules are investigated in this study. The two‐dimensional Schrödinger equation is solved with the Varshni‐screened Coulomb potential (VSCP) model using the well‐known Nikiforov‐Uvarov (NU) method. We obtained the energy eigenvalues and wavefunctions of the system and calculated the energy levels of some diatomic molecules in the m‐arbitrary state in the presence and absence of external magnetic and AB flux fields. The results show that combining the magnetic and AB flux fields eliminates degeneracy. We analyzed and plotted the partition function and other thermal properties in the presence of a magnetic field, an AB field, and a temperature‐dependent term. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) can play an important role in grain refinement, redistribution of second phase and texture evolution. In this study, different rotation speed was employed during FSP to process Mg-Zn-Nd (ZN20) alloy with different grain size, texture and distribution of second phase. Immersion test combined with observation on corrosion morphology was carried out to evaluate the corrosion resistance of ZN20 alloy. After FSP, grain size in the alloy could be refined to 4 μm owning to dynamic recrystallisation, the volume fraction of second phase decreased as the rotation speed increased under the influence of heat input, and strong basal texture could be formed. Finer grain size could play a positive role in improvement of the corrosion resistance by stabilising the corrosion product and acting as a barrier for corrosion cracking. Less second phase and strong basal texture cloud improve the corrosion resistance by reducing the corrosion pits. [ABSTRACT FROM AUTHOR]

Mg-Zn-Ca metal glass shows good promising applications in biomaterials. MAO coating and Ca-P coating was applied on Mg69Zn27Ca4 metal glass in order to improve the alloy biodegradation resistance and biocompatibility. Microstructure observation, electrochemical experiment, immersion experiment and cell cytotoxicity experiment (MG63 cells) were carried out. The result revealed that Ca-P coating exhibited better degradation resistance than MAO coating due to its relatively thick and uniform structure. The cell cytotoxicity showed both coatings showed better bioactivity than the uncoated Mg69Zn27Ca4 metal glass. Moreover, Ca-P-coated samples had better bioactivity than those of MAO coated. Therefore, Ca-P coating improved not only the degradation resistance but also the bioactivity of Mg69Zn27Ca4 metal glass. Ca-P coating has a good promising application on Mg69Zn27Ca4 metal glass. [ABSTRACT FROM AUTHOR]

Currently, orthopaedic implant materials such as titanium alloy are biologically inert materials which are not easily integrated with bone tissues, thus resulting in implantation failures due to the loosening and infection. In this study, bioactive MgXCu(X = 0, 0.1, 0.4, 0.7) coatings were successfully fabricated on Ti6Al4 V substrate by arc ion plating (AIP) technique to improve the antibacterial property. The surface composition and morphology of the coating was characterised by X-ray diffraction, inductively coupled plasma-atomic emission spectrometry (ICP) and scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS). The electrochemical experiment and immersion test showed the corrosion rate of MgXCu coating increased with the addition of Cu element. Antibacterial assays proved that the MgXCu coating could successfully reduce the viability of Staphylococcus aureus (S.aureus) and the thickness of the bacterial film. Consequently, it is concluded that MgXCu coated Ti6Al4 V with antibacterial property is much potential to be used in orthopaedic applications. [ABSTRACT FROM AUTHOR]

Rare earth-containing biodegradable magnesium alloys have attracted many researchers attention due to their good mechanical property and degradation resistance. In this paper, comparative study of the effect of Nd and Y content on the mechanical and biodegradable properties of Mg-2Zn-0.5Zr-xRE alloys was carried out. The results showed that there are mainly α-Mg, Mg12Nd, T-phase ((MgZn)92Nd8) and MgZn2 phase in Mg-2Zn-xNd-0.5Zr alloys. There were mainly α-Mg, I-phase, W-phase and MgZn2 phase in Mg-2Zn-xY-0.5Zr alloys. Minor addition of Nd could both improve the elongation (> 20%) of the alloys and decrease the galvanic corrosion between the matrix and the second phases. However, the addition of Y (1%) was beneficial in improving the ultimate tensile strength (UTS) of the Mg alloys. Minor addition of Y (0.5%) could also improve the degradation resistance of the alloys. The alloys with 0.5% Nd and 0.5% Y have great potential to be used as biomaterials. [ABSTRACT FROM AUTHOR]

Biodegradable Mg-Cu alloys have attracted many researchers attention due to their characteristics of osteogenesis, angiogenesis, and long-lasting antibacterial effects. In this paper, the effect of copper content on the corrosion behaviors and antibacterial properties of binary Mg-Cu alloys was studied. Microstructure characterization, immersion test, electrochemical test and antibacterial test were carried out. The results show that with the increase of Cu content, the corrosion rate of Mg-Cu alloys was increased greatly due to the galvanic corrosion between Mg matrix and Mg2Cu intermetallic phase. The corrosion rate of Mg-0·3Cu alloy was almost 10 times as fast as Mg-0·1Cu alloy in 0·9 wt-% NaCl solution. Antibacterial test showed that Mg-Cu alloys could efficiently reduce the viability of Candida albicans with the addition of Cu above 0·1 wt-%. Mg-0·1Cu has good potential to be used as antibacterial implants due to its good corrosion resistance and antibacterial property. [ABSTRACT FROM AUTHOR]

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The high-temperature oxidation behaviors of Nimonic95 alloy at 800 °C, 900 °C and 1000 °C were studied. The diffusion process of alloying elements in different stages of oxidation was studied and analyzed, and the pre-oxidation process was established. The results showed that multilayer oxide films formed in the air at 800 °C, 900 °C and 1000 °C, the outer layer was mainly Cr 2 O 3 with a small amount of Al 2 O 3 , TiO 2 and composite oxides such as CrTi spinel. The inner layer was mainly Al 2 O 3. Nimonic95 alloy has excellent oxidation resistance at 800 °C and 900 °C, but poor oxidation resistance at 1000 °C and the oxide film peeled off in a short time. The oxidation resistance of Nimonic95 alloy at 1000 °C can be improved significantly by pre-oxidation at 800 °C for 140 h. • The oxidation behavior of Nimonic95 alloy at 800 °C, 900 °C and 1000 °C was studied. • The diffusion mechanism of the alloy elements during different stages of oxidation was revealed. • The mechanism of improving the oxidation resistance of Nimonic95 alloy at 1000 °C by pre-oxidation process was revealed. [ABSTRACT FROM AUTHOR]

Titanium and its alloy are commonly used as surgical staples in the reconstruction of intestinal tract and stomach, however they cannot be absorbed in human body, which may cause a series of complications to influence further diagnosis. Magnesium and its alloy have great potential as surgical staples, because they can be degraded in human body and have good mechanical properties and biocompatibility. In this study, Mg-2Zn-0.5Nd (ZN20) alloy fine wires showed great potential as surgical staples. The ultimate tensile strength and elongation of ZN20 alloy fine wires were 248 MPa and 13%, respectively, which could be benefit for the deformation of the surgical staples from U-shape to B-shape. The bursting pressure of the wire was about 40 kPa, implying that it can supply sufficient mechanical support after anastomosis. Biochemical test and histological analysis illustrated good biocompatibility and biological safety of ZN20 alloy fine wire. The residual tensile stress formed on the outside of ZN20 fine wire during drawing would accelerate the corrosion. The second phase had a negative influence on corrosion property due to galvanic corrosion. The corrosion rate in vitro was faster than that in vivo due to the capsule formed on the surface of ZN20 alloy fine wire., Competing Interests: The authors declare no competing financial interest., (© 2020 [The Author/The Authors].)