Mechanical properties and corrosion behavior of powder metallurgy iron-hydroxyapatite composites for biodegradable implant applications
2016 (English)In: Materials and Design, ISSN 0264-1275, Vol. 109, 556-569 p.Article in journal (Refereed) Published
Nine FeâHA composites were fabricated via powder metallurgy method by varying the amount (2.5, 5, 10Â wt%) and particle size (<Â 1Â ÎŒm, 1â10Â ÎŒm, 100â200Â ÎŒm) of hydroxyapatite (HA) as a bioactive phase in the iron (Fe) matrix. X-ray diffraction did not detect any phase changes in HA after the sintering process. Uniaxial tensile tests measured the strengths of the composites. Polarization and immersion tests estimated the corrosion rates (CR). Yield strength, tensile strength, and ductility of the composites decreased with increasing HA content and decreasing HA particle size, whereas their corrosion rates increased. The strongest composite was Feâ2.5Â wt% HA (100â200Â ÎŒm) with ÏyÂ =Â 81.7Â MPa, ÏuÂ =Â 130.1Â MPa, fracture strain of 4.87%, and CRÂ =Â 0.23Â mmpy. The weakest composite was Feâ10Â wt% HA (<Â 1Â ÎŒm) which did not exhibit plastic deformation, fractured at ÏuÂ =Â 16.1Â MPa with 0.11% strain, and showed the highest CR of 1.07Â mmpy. This study demonstrates how the relative particle size between Fe and HA determines the mechanical and corrosion properties of FeâHA composites, thereby aiding in enhancing future resorbable implant designs. The model can also be used when designing other bioactive composites (i.e. TiâHA, MgâHA) via powder metallurgy.
Place, publisher, year, edition, pages
2016. Vol. 109, 556-569 p.
Biodegradation; Corrosion; Hydroxyapatite; Iron; Mechanical properties; Metallurgy; Metals; Particle size; Powder metallurgy; Powder metals; Sintering; Tensile strength; Tensile testing; X ray diffraction, Bioactive composites; Biodegradable implants; Biodegradable metals; Corrosion behavior; Hydroxyapatite composite; In-vitro; Mechanical and corrosion properties; Uniaxial tensile test, Corrosion rate
Other Materials Engineering
IdentifiersURN: urn:nbn:se:ri:diva-28206DOI: 10.1016/j.matdes.2016.07.092ScopusID: 2-s2.0-84979645281OAI: oai:DiVA.org:ri-28206DiVA: diva2:1083668