Showing 4 results for Magnesium Alloy
R. Jahadi Naeini, M. Sedighi, H. R. Jahedmotlagh,
Volume 33, Issue 3 (3-2015)
Abstract
In this paper, the effect of Equal Channel Angular Pressing (ECAP) process on the structure and mechanical properties of AM30 magnesium alloy was studied. The results showed a considerable effect of ECAP process on creating an ultrafine grain size structure. Scanning Electron Microscope indicated that the grain size dropped from 20.4 µm in the extruded form to 7.2 µm in the first pass and 3.9 µm in fourth pass. The fourth pass presented higher ductility and lower yield stress in comparison with the extruded case. This behavior can be explained based on higher rate of texture softening versus the effects of the grain refinement on strength. The hardness test on the samples cross-section showed an increase in hardness and a uniform strain distribution at higher ECAP passes.
M. Rajabi, R. A. Sedighi , S. M. Rabiee,
Volume 34, Issue 2 (7-2015)
Abstract
In this study, the effect of mechanical alloying on the microstructure and phase constituents of Mg-6Al-1Zn-1Si system was investigated. To understand the thermal behavior, isothermal annealing was performed at three different temperatures of 350, 400 and 450 °C for 1h. The results showed the grain size initially decreases with increasing the milling time up to 35h and then slightly increases. In contrast, the lattice strain increases sharply with increasing the milling time up to 35h and then decreases. Second-phase intermetallic particle Mg2Si was produced during annealing and the amount of this phase was increased with increasing annealing temperature. The mechanical alloying process decreased the formation temperature of Mg2Si.
B. Pourbahari, H. Mirzadeh, M. Emamy,
Volume 37, Issue 4 (3-2019)
Abstract
Microstructural evolutions during the high-temperature annealing of Mg alloys containing Al and Gd and after the extrusion process were evaluated and compared to those of the AZ61 alloy. It was revealed that during exposure at the elevated temperatures, the presence of (Mg,Al)3Gd phase, in the form of fine and dispersed particles in the matrix after the extrusion process, could be favorable for the inhibition of grain growth. It was also found that the Al2Gd particles could not effectively retard the coarsening of grains. On the other hand, the grain growth of AZ61 alloy was found to be problematic, which was related to the dissolution of the Mg17Al12 intermetallic phase at temperatures higher than 300°C. In the Mg alloys containing both Al and Gd elements, the increased thermal stability was observed, which was ascribed to the rise of the melting temperature. Finally, some abnormal grain growth was observed in the presence of Al2Gd phase, which was attributed to the nonuniform pinning of grain boundaries by this intermetallic compound.
N. Safari, M. Toroghinejad, M. Kharaziha, V. Saeedi,
Volume 38, Issue 3 (12-2019)
Abstract
The aim of this study was to fabricate the Mg-1Al-Cu alloys with various amounts of Cu content (0, 0.25, 0.5 and 1 wt.%) using spark plasma sintering (SPS) approach and evaluation of their degradation rate and biological properties. The results indicated that Cu incorporation (0.25 wt.%) significantly diminish degradation rate from 0.039 cm/h in pure Mg to 0.00584 cm/h in Mg-1Al-0.25Cu alloy. In addition, Mg-1Al-0.25Cu alloy could noticeably (1.25 times) promote viability of MG63 cells compared to pure Mg, owing to the optimized ion release. Moreover, the antibacterial activity of Mg-1Al-0.25Cu was considerable. In summary, Mg-1Al-0.25Cu alloy with appropriate degradation rate, good biocompatibility and antibacterial properties can be introduced as a biodegradable orthopedic implant.
