Effect of microstructure and strain on the degradation behavior of novel bioresorbable iron–manganese alloy implants

Advancing the understanding of microstructural effects and deformation on the degradability of Fe–Mn bioresorbable alloys (specifically, Fe–33%Mn) will help address the current problems associated with designing degradable fracture fixation implants for hard tissues. Potentiostatic polarization tests were conducted on a wide variety of metal samples to examine how different deformation processes affect the instantaneous rate of degradation of Fe–Mn alloys. Large-strain machining (LSM), a novel severe plastic deformation (SPD) technique was utilized during these experiments to modify the degradation properties of the proposed Fe–Mn alloy. It was discovered that Fe–33%Mn after LSM with a rake angle of 0° (effective strain = 2.85) showed the most promising increase in degradation rate compared to as-cast, annealed, and additional deformation conditions (rolled and other LSM parameters) for the same alloy. The mechanisms for enhancement of the corrosion rate are discussed. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 738–745, 2015.