Microstructure and mechanical properties of extruded profiles made from pure magnesium powders

Abstract

Magnesium-based biomaterials are good candidates as a new generation of biodegradable metals since magnesium (Mg) can dissolve in body fluid. Therefore, implanted Mg can degrade during the healing process, and if the degradation rate is controlled no debris after completion of healing is expected. Besides its biocompatibility, inherent mechanical properties of Mg are very similar to those of human bone. This paper is focused on the possibility to prepare the pure Mg material from powders with further intention to use it as a biodegradable implant. Powders were consolidated via cold compaction to prepare the extrusion billets which were subsequently directly extruded to final profiles at a controlled temperature to avoid the formation of the thick oxide layer. The microstructure is revealed through SEM, SEM--EBSD, TEM, and HRTEM and mechanical properties are determined via a uniaxial tensile test. Results are compared with Mg ingot and WE43 alloy, which is commercially used for biodegradable (biocompatible) material. K e y w o r d s : magnesium, powder metallurgy, biocompatibility, microstructure, mechanical properties

Hot extrusion of magnesium/hydroxyapatite composites prepared by powder metallurgy

“…The corrosion rate of the pure Mg sample extruded from the as-cast state is characterized by the highest corrosion rate, almost one-third higher compared to that of the composite material. Nevertheless, the high corrosion rate was caused by numerous MgO phases, which acted as cathode areas and accelerated the corrosion by microgalvanic cells [25].…”

“…The ideal method for the preparation of composite materials seems to be powder metallurgy [24]. It offers few methods for effective powder homogenization and powder compacting [25]. Extrusion is the standard way of processing magnesium-based materials [26].…”

Effects of Gd and heat treatments on mechanical properties of Mg-xGd-1Zn-0.4Zr alloys

“…Biomedical magnesium alloys have good biodegradability, biocompatibility, physical and mechanical properties, and hence, they can be used for orthopedic fixation, cardiovascular stents, and the other short-term implant fields [1][2]. They provide temporary support and progressive degradation during service, which eliminate subsequent surgery and reduce the risk of local inflammation after long-term implantation [3][4][5]. Therefore, magnesium alloys are expected to replace the traditional non-degradable metals as new generation biomedical implanted materials.…”