Production of Biodegradable High‐Entropy Zn–Fe–Mg–Mn–Ti–Si Alloy by Powder Injection Molding Method

Herein, biocompatible and biodegradable high‐entropy Zn – Fe – Mg – Mn – Ti – Si alloys are produced by mechanical alloying–powder injection molding method for temporary implant applications. Mg, Fe, and Zn alloys are biodegradable metals. Mg alloys biodegrade too fast with H 2 evolution. Biodegradation rate of Fe alloys is too slow. Zn alloys show biodegradation rates in the middle of Mg and Fe alloys. Low ductility and formation of intermetallics are the main drawbacks of the Zn alloys. Formation of ductile face‐centered or body‐centered‐cubic phases and elimination of intermetallics by formation of solid solution can enhance the ductility. High‐entropy alloys tend to forma a solid solution instead of brittle intermetallics. Mechanical alloying–powder injection molding method is used in order to prevent formation of intermetallics. Powder injection molding can reduce the segregation and provide homogeneous microstructure. Initially, metal powders are mechanically alloyed. Polymer binder consists of polyethylene, paraffin, and stearic acid. Feedstock consists of 45% of binder and 55% of alloy powder. After the injection, binder is removed. Sintering is carried out at 320 °C. Mechanical properties, corrosion properties, and biodegradation properties are characterized. In addition, first‐principles‐based density function theory code is used in order to calculate the mechanical properties.