Structure and Corrosion-Electrochemical Behavior of Bioresorbable Alloys Based on the Fe–Mn System

Effect of Thermomechanical Treatment on Structure and Functional Fatigue Characteristics of Biodegradable Fe-30Mn-5Si (wt %) Shape Memory Alloy

“…However, pure iron dissolves at a low rate (0.10 mm/year), and even the introduction of electrochemically active manganese into the composition without additional impact on the alloy structure only slightly increases the biodegradation rate (Fe-30Mn, 0.11 mm/year) [ 14 ] in Hanks’ solution [ 15 ], which is insufficient for the complete elimination of the alloy components from the body after the completion of the damaged tissue regeneration process [ 1 , 5 ]. However, the biodegradation rate of the Fe-30Mn alloy can be increased several times after the homogenization of its structure by conducting isothermal annealing for 1 h followed by quenching in water [ 16 , 17 ].…”

“…At a certain manganese content (28–33 wt %), the introduction of 4–6 wt % Si to the alloy composition leads not only to the hardening of the alloys [ 18 ] but also facilitates the realization of the shape memory effect [ 17 , 19 , 20 ]. Moreover, the heat treatment of the Fe-30Mn-5Si alloy [ 17 ], which ensured the stabilization of the martensitic structure, made it possible to significantly reduce the martensitic start ( M s ) and finish ( M f ) temperatures: 60 °C and below 60 °C, respectively, in comparison with the Fe-(23-26)Mn-5Si. According to [ 17 ], this is due to the crystal lattice deformation caused by high Mn content, leading to a slowdown in the γ—ε transformation and/or a high austenite volume fraction.…”

“…Moreover, the heat treatment of the Fe-30Mn-5Si alloy [ 17 ], which ensured the stabilization of the martensitic structure, made it possible to significantly reduce the martensitic start ( M s ) and finish ( M f ) temperatures: 60 °C and below 60 °C, respectively, in comparison with the Fe-(23-26)Mn-5Si. According to [ 17 ], this is due to the crystal lattice deformation caused by high Mn content, leading to a slowdown in the γ—ε transformation and/or a high austenite volume fraction.…”

“…Studies of Fe-(23...30) Mn-5Si alloys (wt %) described in [ 16 , 17 , 24 ] showed the possibility of achieving optimal characteristics by implementing certain regimes of thermal and thermomechanical treatment leading to the rise of biodegradation rate from 0.4 to 0.8 mm/year, the decrease in the elastic modulus from 120 to 97 GPa, and a decrease M s temperature from 70 to 38 °C. The best characteristics were obtained for the Fe-30Mn-5Si alloy [ 24 ].…”

“…Given the above and based on the results obtained in [ 16 , 17 , 24 ], the main goal of this work is to study the Fe-30Mn-5Si alloy fatigue behavior features in the initial state (homogenized and quenched) and after thermomechanical treatment (TMT) using mechanical cyclic tests in air and Hanks’ solution, the study of Young’s modulus temperature dependence in the temperature range above and close to the M s to verify the existence of lattice softening effect, which is characteristic of shape memory alloys, and the role of martensitic transformation in corrosion fatigue failure of the alloy.…”