TY - JOUR

T1 - Revisiting the tolerance limit of Fe impurity in biodegradable magnesium

AU - Zhang, Yaping

AU - Huang, Yuanding

AU - Chen, Xiang

AU - Luthringer-Feyerabend, Bérengère

AU - Xue, Ju

AU - Zander, Daniela

AU - Willumeit-Römer, Regine

AU - Kainer, Karl Ulrich

AU - Hort, Norbert

PY - 2022/4/15

Y1 - 2022/4/15

N2 - The existence of iron impurity in magnesium (Mg) is conventionally deemed detrimental to the corrosion resistance against the inorganic solutions, especially over its tolerance limit. We deliberately investigated the biodegradation properties of pure Mg with different contents of Fe by immersing in DMEM+10% FBS. Surprisingly, the impurity of Fe, even its content higher than the tolerance limit previously determined by immersion in inorganic solutions such as NaCl, has no negative effect on the degradation of pure Mg. Pure Mg with a high content of Fe impurity even retains good biocompatibility. Detailed microstructural analyses decipher that the severe local micro-galvanic corrosion caused by the Fe impurity meanwhile promotes the formation of compact Ca-rich corrosion product layer on the top surface, protecting the adjacent Mg matrix from being further corroded. The present discovery provides new insights in designing biodegradable Mg alloys, especially pursuing high-level impurity doping without deteriorating the biocompatibility.

AB - The existence of iron impurity in magnesium (Mg) is conventionally deemed detrimental to the corrosion resistance against the inorganic solutions, especially over its tolerance limit. We deliberately investigated the biodegradation properties of pure Mg with different contents of Fe by immersing in DMEM+10% FBS. Surprisingly, the impurity of Fe, even its content higher than the tolerance limit previously determined by immersion in inorganic solutions such as NaCl, has no negative effect on the degradation of pure Mg. Pure Mg with a high content of Fe impurity even retains good biocompatibility. Detailed microstructural analyses decipher that the severe local micro-galvanic corrosion caused by the Fe impurity meanwhile promotes the formation of compact Ca-rich corrosion product layer on the top surface, protecting the adjacent Mg matrix from being further corroded. The present discovery provides new insights in designing biodegradable Mg alloys, especially pursuing high-level impurity doping without deteriorating the biocompatibility.

KW - Biocompatibility

KW - Corrosion tolerance limit

KW - Degradation

KW - Fe impurity

KW - Magnesium

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85123737093&partnerID=8YFLogxK

U2 - 10.1016/j.scriptamat.2022.114509

DO - 10.1016/j.scriptamat.2022.114509

M3 - Journal articles

AN - SCOPUS:85123737093

VL - 212

JO - Scripta Materialia

JF - Scripta Materialia

SN - 1359-6462

M1 - 114509

ER -