Microstructural Evolution and Properties of a Hot Extruded and HPT‐Processed Resorbable Magnesium WE43 Alloy

Disks of an extruded magnesium WE43 alloy are processed by high‐pressure torsion (HPT) and the evolutions of microstructure and mechanical properties are investigated in detail. Excellent grain refinement is achieved by HPT processing with a reduction in grain size from an initial value of ≈12 μm to a final value of ≈200–300 nm after 10 turns. The microhardness increases significantly with HPT processing but low hardness values are recorded at the centers of the disks. The tensile strength initially increases and then decreases while the elongation decreases. Observations of the fracture surfaces reveal a corresponding transition of the fracture mode from ductile to brittle. Microstructure evolution of HPT‐processed resorbable WE43 alloy is investigated. A WE43 alloy with an initial grain size of ≈12 µm is processed by HPT to produce an ultrafine‐grained microstructure and the sub‐grain size is ≈200–300 nm after 10 turns. The microhardness shows significant improvement with increasing dislocation density. The tensile strength firstly increases and then decreases, while the elongation decreases after HPT deformation.