Effect of rotary swaging and subsequent aging on the implant-relevant properties of magnesium alloy WE43

Abstract

The magnesium alloy WE43 were pre-strained by rotary swaging (RS) with a final temperature of 350°C. RS led to a significant grain refinement with the formation of a predominantly subgrain structure. The average size of the structural elements decreased up to 450±50 nm after RS. In addition, the RS-induced precipitation of intermetallic Mg41Nd5 particles with an average size of 210±13 nm was observed. Subsequent heat treatment caused the average size of structural elements and intermetallic particles to grow to 781±88 nm and 494±51 nm, respectively. After RS, the ultimate tensile strength (UTS) of the alloy rose to 363±2 MPa with tensile elongation of 11.4±0.6%. After heat treatment, the UTS of the alloy increased to 376±9 MPa, with some drop of tensile elongation to 7.6±0.4%. Interestingly, the biocorrosion resistance of the alloy was not compromised by RS, while subsequent heat treatment of the swaged alloy reduced its biodegradation rate. No significant differences in the biocompatibility of the alloy WE43 between different microstructural states were observed. It was found that RS with subsequent aging of the alloy WE43 reduces the adhesion of yeast to its surface, which in the long term may reduce the risk of infectious complications after orthopedic surgery.