Production of metal matrix composite biomaterials for implant applications

In this thesis, the production and characterization of biodegradable (bioresorbable) novel particule reinforced Fe, Mg, Zn metal matrix composites for biomedical implant (hard tissue) applications were carried out. In this thesis, Fe, Zn, Mg based TiO2, TCP, boron, and carbon nanotube particule reinforced metal matrix composites were prepared. Fe, Zn, Mg based TiO2, TCP, boron and carbon nanotube particule reinforced metal matrix composites were prepared by traditional powder metallurgy (press-sintering) method. In this thesis, elemental Fe, Mg, Zn alloy powders and TiO2, TCP, boron and carbon nanotube particule reinforced metal matrix composites were prepared by mechanical alloying (ball mill) method. Then, the green composite specimens were prepared by hydraulic pressing. Then, the green compacts were sintered at 1250 °C (Fe alloys), or 320 °C (Zn alloys), or 500 °C (Mg alloys) for 1 hou in vacuumr. The effects of alloying elements and particule reinforcements on the several properties of the particule reinforced Fe, Mg or Zn metal matrix composite specimens were investigated. The microstructureand mechanical properties of the produced composite specimens was investigated using destructive (wear test, hardness test) and non-destructive (ultrasonic testing,) tests. Biodegradation (weight loss) behaviour of the Fe, Mg, and Zn matrix composite materials was investigated in simulated body fluid (SBF) solution with pH of 6.6 by using static immersion tests. Additionally, the electrochemical corrosion behaviour of the Fe, Mg, and Zn matrix composite materials was investigated in simulated body fluid (SBF) solution with pH of 6.6 by using open circuit potential, Tafel and linear polarization tests. Biocompatibility of the Fe, Mg and Zn based metal matrix composite materials was also studied. Properties of the Fe, Mg, Zn matrixcomposite specimens was investigated by computational materials science based programmes (CASTEP, LAMMPS and Thermo-Calc). Mechaical properties were studied by Quantum mechanics based first principles and density functional theory based CASTEP software programme and Newton mechanics based molecular Dynamics based LAMMPS software programme. First principles theory considers only electrons and atom core. Molecular Dynamics theory considers atoms as a base particle, do not consider electrons and atom core. Phase diagrams of the materials were studied by calculated phase diagrams (CALPHAD) based Thermo-Calc software programme..