Surface morphology investigation of a biodegradable magnesium alloy

Download
2015
Tahmasebifar, Aydin
In this study, the effect of manufacturing conditions (i.e. compaction pressure, sintering temperature and time) on physical, mechanical and electrochemical properties of Mg alloy discs as samples of biomedical implants prepared using powder forming technology were investigated. The main motivation of this study was to achieve the manufacturing of porous and micro-surface textured Mg-based biomedical implants with good mechanical and electrochemical properties. A Box-Behnken and Full Factorial experimental design was used in experimentation. Relative densities of the plates were obtained experimentally. They varied from 69.7±1% to 81.5±4%. According to ANOVA (Analysis of variances) test, manufacturing conditions did not affect the relative density significantly except the compaction pressure level. The bending strength was in the range of 30.3±2 MPa and 53.7±1 MPa. Compaction pressure led to an increase in the bending strength while sintering temperature and time decreased. Electrochemical tests were conducted using Hank’s solution, DMEM (Dulbecco's Modified Eagle's Medium) and 10% FBS (Fetal Bovine Serum)+DMEM. The lowest and the highest corrosion potentials were measured in Hank’s and 10% FBS+DMEM solutions, respectively. Pitting corrosion was detected on the surface of Mg alloy discs. In Hank’s solution, pitting corrosion was observed more than DMEM and 10% FBS+DMEM. The discs with smooth surfaces also showed lower corrosion resistance than the discs with porous and micro-textured surfaces in the presence of FBS. It was concluded that the manufacturing of porous and micro-surface textured Mg based biomedical implant using powder forming process was reasonable due to the convenience of near net shape production with sufficient material properties. Also, the cell culture studies showed that micro texture and roughness positively affected cell adhesion, proliferation and osteogenic activity. AZ91D-Mg alloy plates showed good cytocompatibility with higher cell proliferation compared to control groups at each incubation time period.

Suggestions

Mechanical, electrochemical and biocompatibility evaluation of AZ91D magnesium alloy as a biomaterial
Tahmasebifar, Aydin; KAYHAN, Said Murat; Evis, Zafer; Tezcaner, Ayşen; Cinici, Hanifi; Koc, Muammer (2016-12-05)
In this study, the effect of manufacturing conditions (i.e. compaction pressure, sintering temperature and time) on physical, mechanical and electrochemical properties of Mg alloy discs were investigated. The main motivation of this study was to achieve the manufacturing of porous and micro-surface textured Mg-based biomedical implants with good mechanical and electrochemical properties. A Box-Behnken and Full Factorial experimental design was used in experimental investigations. Relative densities of the f...
Manufacturing, mechanical and microstructural characterization of AZ91D magnesium alloy for biomedical applications
Kayhan, Said Murat; Evis, Zafer; Koç, Muammer; Department of Engineering Sciences (2015)
In this study, the microstructural and mechanical properties of the Mg-based implant samples prepared via powder metallurgy route were investigated. Moreover, the biological response of the Mg-based implant samples was investigated. AZ91D Mg alloy discs with smooth and textured surfaces were manufactured under compaction pressures of 25 and 40 MPa at 150⁰C. They were then sintered at 380⁰C for 30 and 150 mins. The microstructural evaluation was conducted through SEM and light microcopy images. As compaction...
Characterization and fatigue behavior of Ti-6Al-4V foams
Aşık, Emin Erkan; Bor, Şakir; Department of Metallurgical and Materials Engineering (2012)
Porous Ti-6Al-4V alloys are widely used in the biomedical applications for hard tissue implantation due to its biocompatibility and elastic modulus being close to that of bone. In this study, porous Ti-6Al-4V alloys were produced with a powder metallurgical process, space holder technique, where magnesium powders were utilized in order to generate porosities in the range of 50 to 70 vol. %. In the productions of Ti-6Al-4V foams, first, the spherical Ti-6Al-4V powders with an average size of 55 μm were mixed...
Production and characterization of surface treated biomedical Ti6Al7Nb alloy foams /
Bütev, Ezgi; Bor, Şakir; Esen, Ziya; Department of Metallurgical and Materials Engineering (2015)
The current study was undertaken to investigate the production and surface processing of biomedical Ti6Al7Nb alloy foams. Space holder method was utilized to manufacture foams with varying porosities around 53.0-73.0 vol. % via evaporation of magnesium from compacted Ti6Al7Nb-Mg powder mixtures. Bioactivities of foam surfaces were further enhanced by obtaining sodium rich phases using NaOH alkali-heat treatment method. Moreover, untreated and surface treated foams were tested in simulated body fluid (SBF) i...
Thermal characterization of composites of polyamide-6 and polypropylene involving boron compounds via direct pyrolysis mass spectrometry
İşbaşar Afacan, Güllü Ceyda; Hacaloğlu, Jale; Yılmazer, Ülkü; Department of Polymer Science and Technology (2013)
In this work, the effects of addition of boron compounds, boron phosphate (BPO4), zinc borate (ZnB), borosilicate (BSi) and lanthanum borate (LaB), on thermal degradation characteristics of composites of polyamide 6 (PA6) and polypropylene (PP) are analyzed via Direct Pyrolysis Mass Spectrometry (DP-MS) technique. The composites of PA6 involve nitrogen containing flame retardants, melamine (Me) or melamine cyanurate (MC); or phosphorus containing flame retardant, aluminum diethylphosphinate (AlPi), with or ...
Citation Formats
A. Tahmasebifar, “Surface morphology investigation of a biodegradable magnesium alloy,” Ph.D. - Doctoral Program, Middle East Technical University, 2015.