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A comprehensive evaluation between the efficiency of different treatments in modifying the properties and behavior of magnesium alloys as degradable biomaterials
Author(s) -
Homayun B.,
Afshar A.
Publication year - 2017
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/maco.201709453
Subject(s) - materials science , dissolution , corrosion , intergranular corrosion , alloy , metallurgy , grain boundary , magnesium alloy , polarization (electrochemistry) , magnesium , microstructure , chemical engineering , chemistry , engineering
The addition of alloying elements to magnesium leads to microstructural refinement and improves its properties. However, this strategy is accompanied by another concurrent phenomenon − that is − intergranular segregation and the formation of secondary phases in grain boundaries, deteriorating the properties. In this work, the efficacy of two main factors on modifying the mechanical properties and corrosion behavior of Mg‐4Zn‐1Al‐0.2Ca alloy was investigated separately: 1) dissolution of secondary phases; and 2) grain refinement. Based on the results, heat treatment of the as‐cast alloy can increase the UTS from 174.4 to 213.2 MPa, decrease the corrosion current density from 81 to 49 μA/cm 2 , and enhance the polarization resistance from 1410 to 1780 Ω cm 2 . While, the UTS of the as‐rolled sample increased to 355 MPa, its corrosion current density decreased to 11 μA/cm 2 , and its polarization resistance improved to 2078 Ω cm 2 , indicating that compared to dissolution heat treatment, microstructural refinement plays a considerably more effective role in modifying the alloy's behavior. Cytotoxicity and cell adhesion studies also implied on the biosafety of this material in vitro.