Bio-corrosion impacts on mechanical integrity of ZM21 Mg for orthopaedic implant application processed by equal channel angular pressing

Abstract

The mechanical integrity of rolled ZM21 Mg was improved by equal channel angular pressing (ECAP) to function as a potential biodegradable bone screw implant. Electron backscattered diffraction (EBSD) revealed deformed grains of 45 µm observed in rolled ZM21 Mg. They were transformed to equiaxed fine grains of 5.4 µm after 4th pass ECAP. The yield strength of rolled and ECAPed ZM21 Mg alloys were comparable. In contrast, 4th pass ZM21 Mg exhibited relatively higher elongation when compared to rolled sample. The mechanical properties of rolled and ECAPed ZM21 Mg were dependant on both grain refinement and crystallographic texture. The rolled and 4th pass ECAPed tensile samples exhibited nonlinear deterioration of mechanical properties when tested after 7, 14, 21 and 28 days immersion in Hank’s solution. The evaluation signifies that regardless their processing condition, ZM21 Mg alloys are suitable for surgical areas that requires high mechanical strength. In addition, the 4th pass ECAP samples were viable to MG-63 cells proving themselves to be promising candidates for future in vivo studies.

An Overview on the Effect of Severe Plastic Deformation on the Performance of Magnesium for Biomedical Applications

“… Corrosion rate reported in samples of magnesium processed via ECAP [ 52 , 55 , 56 , 57 , 58 , 59 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 69 , 71 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 82 , 83 , 84 , 85 , 86 , 87 ] and HPT [ 19 , 88 , 90 , 91 , 92 , 93 , 94 , 95 , 97 , 98 , 99 , 100 ] plotted as a function of the grain size. …”

“… Corrosion rate vs. flow stress of magnesium and its alloys before and after SPD processing. Data from the literature [ 19 , 57 , 58 , 59 , 64 , 66 , 70 , 72 , 76 , 77 , 78 , 79 , 80 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 90 , 91 , 92 , 94 , 100 ]. …”

Evaluation of 3D printed PEEK and other 3D printed biocompatible materials as healthcare devices

“…In this study L9292 murine fibroblast cells were used and cultured in Dulbecco's Modified Eagle Medium (DMEME) supplemented with 10% Fetal bovine serum (FBS), 1% glutamine and 1% antibioticantimycotic solution. Cells were maintained at 37 0 C and 5% CO2 in a humidified atmosphere throughout the experiments (13).…”