Shape Memory Characteristics of Silver-Added Fe-30Mn-6Si Alloy

摘要

Fe-30Mn-6Si ternary alloy is promising for biodegradable applications in recent years due to its high biodegradability and moderate shape memory performance. In this study, the effects of silver addition (1.2 wt%) on the martensitic transformation temperatures, mechanical properties, and shape recovery performance of solution-treated Fe-30Mn-6Si alloy were investigated. Contrary to the as-cast condition, silver-microalloying caused a decrease in the martensite volume fraction in solution-treated samples. Silver-added alloy showed lower 0.2% offset compressive strength and higher shape recovery rate compared to ternary alloy owing to its martensite start temperature being close to the room (deformation) temperature. Better shape recovery performance was also attributed to the austenite-strengthening effect of the Ag-rich precipitates. The tested Fe-30Mn-6Si-1.2Ag alloy exhibited full shape recovery for a 4% compressive pre-strain after three thermo-mechanical training cycle.