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1.
For the purpose of developing biodegradable magnesium alloys with suitable properties for biomedical applications, Mg–Zn–Ca–Cu metallic glasses were prepared by copper mold injection methods. In the present work, the effect of Cu doping on mechanical properties, corrosion behavior, and glass-forming ability of Mg66Zn30Ca4 alloy was studied. The experimental findings demonstrated that the incorporation of Cu decreases the corrosion resistance of alloys, but increases the microhardness and degradation rate slightly. However, the addition of a trace amount of Cu can make the samples have antibacterial properties. Therefore, Mg–Zn–Ca–Cu has great advantages in clinical implantation and is the potential implant material. 相似文献
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《Calphad》2019
Mg–Zn–Ca alloys are representative Mg alloys with high formability at room temperature. Their high formability is thought to be related to slip, twinning, and recrystallization of the alloys, but the detailed mechanisms have not yet been clarified. To enable atomistic simulations for investigating those behaviors, an interatomic potential for the Mg–Zn–Ca ternary system was developed. The development was based on the second nearest-neighbor modified embedded-atom method formalism, combining previously developed Mg–Zn and Mg–Ca potentials with the newly developed Zn–Ca binary potential. The Zn–Ca and Mg–Zn–Ca potentials reproduce structural, elastic, and thermodynamic properties of compounds and solution phases of relevant alloy systems in reasonable agreement with experimental data, first-principles and CALPHAD calculations. The applicability of the developed potentials is demonstrated through calculations of the effects of Zn and Ca solutes on the generalized stacking fault energy for various slip systems, segregation energy on twin boundaries, and volumetric misfit strain. 相似文献
4.
王芬 《武汉理工大学学报(材料科学英文版)》2005,20(Z1)
1Introduction Harmfulbacteriaexistanywhereintheworldsuchas soil,air,water,surfacesofobjectsandourskins,etc.Thenumberofbacteriumisenormous,withmanydiffer entspecies.Theyhavethreatenedthehealthofhuman beingsseriously.Withthedevelopmentofeconomyand environme… 相似文献
5.
以工业偏钛酸、硫酸锌、氨水为主要原料,用直接沉淀法并进行热处理得到钛酸锌粉体,并用XRD对产物成分进行了检测。结果表明,不同的锌钛比对钛酸锌(ZnO-TiO2)体系的成分有较大影响。 相似文献
6.
采用喷射成形技术制备了Al1 0 Zn2 .9Mg1 .7Cu高强高韧铝合金沉积坯件 ,研究了喷射成形制备过程中各工艺参数对沉积坯件的成形性、显微组织、致密度的影响 ,确定了适当的工艺参数 ,研究了沉积坯件的热挤压及热处理工艺 ,对材料的组织进行了分析并对不同状态的材料性能进行了比较。研究结果表明 :当喷射成形工艺参数合理时 ,沉积坯件具有良好的成形性与致密度 ,在随后的热挤压过程中 ,通过较低的挤压比即可使材料达到全致密 ;通过对合金进行适当的热处理 ,材料的极限抗拉强度达到 810MPa ,同时延伸率保持在 8%~ 11% ,该材料是一种理想的轻质高强结构材料。 相似文献
7.
通过适当的工艺措施,采用Bridgman法生长了直径为30mm的X射线及γ射线探测器级的Cd.9Zn0.1Te晶锭.测试结果表明:该晶锭结晶质量良好,位错密度低,成分均匀,杂质含量低,红外透过率和电阻率都十分接近本征Cd.9Zn0.1Te的值.并从晶体的生长特性、缺陷和杂质的角度,分析了生长高性能晶体的条件,研究了生长Cdl-xZnxTe晶体的x值与缺陷和杂质浓度之间的关系. 相似文献
8.
T. S. Lee S. B. Lee J. M. Kim J. S. Kim S. H. Suh J. H. Song I. H. Park S. U. Kim M. J. Park 《Journal of Electronic Materials》1995,24(9):1057-1059
In order to improve the Zn homogeneity along the axial direction of CdZnTe boule, we have employed a modified Bridgman technique
using a (Cd, Zn) alloy source in communication with the melt, whose temperature has been gradually changed from 800 to 840°C
during growth. Electron probe microanalysis (EPMA) measurements of Zn composition in the boule shows an excellent homogeneity
of Zn along the axis of the CdZnTe boule compared with results in a boule grown by using a fixed source temperature. We have
performed a numerical simulation to obtain the approximate temperatures of additional heating and cooling needed to improve
the radial Zn homogeneity. CdZnTe boule has been grown by seeded vertical Bridgman furnace with two zones of heater and cooler.
Ultraviolet/visible spectroscopic measurements of Zn composition over the length of the boule indicate that the radial distribution
of Zn composition is very homogeneous in the body region of the boule, where the radial variation of Zn composition is ±0.0005. 相似文献
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10.
The employment of the Zn(Se,Te) pseudo-graded contacting scheme to p-type ZnSe-based alloys contributes directly to the recent
demonstration of room temperature continuous-wave operation of II– VI green-blue laser diodes. Contact ohmicity is maintained
down to cryogenic temperatures which enabled the investigation of electrical transport properties associated with the p-type
nitrogen-doped ZnSe, Zn(S,Se), and (Zn,Mg)(S,Se). The observation of both persistent photoconductivity and a metastable population
of holes which are in thermodynamic equilibrium with hydrogenic acceptors having reduced activation energy suggests the presence
of a DX-like behavior for holes in p-type (Zn,Mg)(S,Se). 相似文献