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DDC: 620 × Type: Article × Subject: mechanical properties × Subject: microstructure ×

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Now showing 1 - 4 of 4
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    Antibacterial Ti-Cu alloy with enhanced mechanical properties as implant applications
    (Bristol : IOP Publishing, 2020) Yi, ChangBo; Ke, ZunYun; Zhang, Lei; Tan, Jun; Jiang, YeHua; He, ZhengYuan
    The service life as hard tissue implantation for clinical application needs compatible mechanical properties, e.g. strength, modulus, etc, and certain self-healing in case of internal infection. Therefore, for sake of improving the properties of Ti-Cu alloy, the microstructure, mechanical properties, corrosion resistance and antibacterial properties of Ti-xCu alloy (x = 2, 5, 7 and 10 wt.%) prepared by Ar-arc melting followed by heat treatment were studied. The results show that the Ti-Cu alloy was mainly composed of α-Ti matrix and precipitated Ti2Cu phase. The Cu element mainly accumulates in the lamellar structure and forms the precipitated Ti2Cu phase. As the increase of Cu content, the lamellar Ti2Cu phase increases, the compressive strength and elastic modulus also were altered. The Ti-7Cu alloy exhibited the higher compressive strength (2169 MPa) and the lower elastic modulus (108 GPa) compared with other Ti-Cu alloys. The corrosion resistance of Ti-xCu alloys increases with the increase of Cu content. When the Cu content was greater than 5 wt.%, the value of corrosion current density for Ti-Cu alloy was less than 1 μAcenterdotcm−2, which is also significantly lower than that of CP-Ti. The antibacterial test revealed that only the Ti-Cu alloy with 5 wt.% or greater Cu content could display a strong antibacterial rate against E. coli and S. aureus. Therefore, the prepared Ti-7Cu alloy via heat treatment showed excellent mechanical properties, corrosion resistance, and antibacterial properties, which would meet the replacement of human hard tissue and clinical applications.
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    Phase Formation, Microstructure and Mechanical Properties of Mg67Ag33 as Potential Biomaterial
    (Basel : MDPI, 2021) Kosiba, Konrad; Prashanth, Konda Gokuldoss; Scudino, Sergio
    The phase and microstructure formation as well as mechanical properties of the rapidly solidified Mg67Ag33 (at. %) alloy were investigated. Owing to kinetic constraints effective during rapid cooling, the formation of equilibrium phases is suppressed. Instead, the microstructure is mainly composed of oversaturated hexagonal closest packed Mg-based dendrites surrounded by a mixture of phases, as probed by X-ray diffraction, electron microscopy and energy dispersive X-ray spectroscopy. A possible non-equilibrium phase diagram is suggested. Mainly because of the fine-grained dendritic and interdendritic microstructure, the material shows appreciable mechanical properties, such as a compressive yield strength and Young’s modulus of 245 ± 5 MPa and 63 ± 2 GPa, respectively. Due to this low Young’s modulus, the Mg67Ag33 alloy has potential for usage as biomaterial and challenges ahead, such as biomechanical compatibility, biodegradability and antibacterial properties are outlined.
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    Ti/Al multi-layered sheets: Differential speed rolling (Part B)
    (Basel : MDPI, 2016) Romberg, Jan; Freudenberger, Jens; Watanabe, Hiroyuki; Scharnweber, Juliane; Eschke, Andy; Kühn, Uta; Klauß, Hansjörg; Oertel, Carl-Georg; Skrotzki, Werner; Eckert, Jürgen; Schultz, Ludwig
    Differential speed rolling has been applied to multi-layered Ti/Al composite sheets, obtained from accumulative roll bonding with intermediate heat treatments being applied. In comparison to conventional rolling, differential speed rolling is more efficient in strengthening the composite due to the more pronounced grain refinement. Severe plastic deformation by means of rolling becomes feasible if the evolution of common rolling textures in the Ti layers is retarded. In this condition, a maximum strength level of the composites is achieved, i.e., an ultimate tensile strength of 464 MPa, while the strain to failure amounts to 6.8%. The deformation has been observed for multi-layered composites. In combination with the analysis of the microstructure, this has been correlated to the mechanical properties.
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    Ti/Al multi-layered sheets: Accumulative roll bonding (Part A)
    (Basel : MDPI, 2016) Romberg, Jan; Freudenberger, Jens; Bauder, Hansjörg; Plattner, Georg; Krug, Hans; Holländer, Frank; Scharnweber, Juliane; Eschke, Andy; Kühn, Uta; Klauß, Hansjörg; Oertel, Carl-Georg; Skrotzki, Werner; Eckert, Jürgen; Schultz, Ludwig
    Co-deformation of Al and Ti by accumulative roll bonding (ARB) with intermediate heat treatments is utilized to prepare multi-layered Ti/Al sheets. These sheets show a high specific strength due to the activation of various hardening mechanisms imposed during deformation, such as: hardening by grain refinement, work hardening and phase boundary hardening. The latter is even enhanced by the confinement of the layers during deformation. The evolution of the microstructure with a special focus on grain refinement and structural integrity is traced, and the correlation to the mechanical properties is shown.