Open AccessHydrolytic Expansion Induces Corrosion Propagation for Increased Fe Biodegradation
Author(s) -
Cijun Shuai,
Sheng Li,
Shuping Peng,
Youwen Yang,
Chengde Gao
Publication year - 2020
Publication title -
international journal of bioprinting
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.014
H-Index - 24
eISSN - 2424-7723
pISSN - 2424-8002
DOI - 10.18063/ijb.v6i1.248
Subject(s) - degradation (telecommunications) , hydrolysis , corrosion , biodegradation , materials science , matrix (chemical analysis) , hydrolytic degradation , chemical engineering , composite material , chemistry , organic chemistry , telecommunications , engineering , computer science
Fe is regarded as a promising bone implant material due to inherent degradability and high mechanical strength, but its degradation rate is too slow to match the healing rate of bone. In this work, hydrolytic expansion was cleverly exploited to accelerate Fe degradation. Concretely, hydrolyzable Mg2Si was incorporated into Fe matrix through selective laser melting and readily hydrolyzed in a physiological environment, thereby exposing more surface area of Fe matrix to the solution. Moreover, the gaseous hydrolytic products of Mg2Si acted as an expanding agent and cracked the dense degradation product layers of Fe matrix, which offered rapid access for solution invasion and corrosion propagation toward the interior of Fe matrix. This resulted in the breakdown of protective degradation product layers and even the direct peeling off of Fe matrix. Consequently, the degradation rate for Fe/Mg2Si composites (0.33 mm/y) was significantly improved in comparison with that of Fe (0.12 mm/y). Meanwhile, Fe/Mg2Si composites were found to enable the growth and proliferation of MG-63 cells, showing good cytocompatibility. This study indicated that hydrolytic expansion may be an effective strategy to accelerate the degradation of Fe-based implants.