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The Fe-Mn-Si shape memory alloys are considered promising materials for the biodegradable bone implant application since their functional properties can be optimized to combine bioresorbability with biomechanical and biochemical compatibility with bone tissue. The present study focuses on the fatigue and corrosion fatigue behavior of the thermomechanically treated Fe-30Mn-5Si (wt %) alloy compared to the conventionally quenched alloy because this important functionality aspect has not been previously studied. Hot-rolled and water-cooled, cold-rolled and annealed, and conventionally quenched alloy samples were characterized by X-ray diffraction, transmission electron microscopy, tensile fatigue testing in air atmosphere, and bending corrosion fatigue testing in Hanks’ solution. It is shown that hot rolling at 800 °C results in the longest fatigue life of the alloy both in air and in Hanks’ solution. This advantage results from the formation of a dynamically recrystallized γ-phase grain structure with a well-developed dislocation substructure. Another important finding is the experimental verification of Young’s modulus anomalous temperature dependence for the studied alloy system, its minimum at a human body temperature, and corresponding improvement of the biomechanical compatibility. The idea was realized by lowering Ms temperature down to the body temperature after hot rolling at 800 °C.

Influence of reagent ratio on the composition of products of the reaction between 1,1,2,2-tetrabromoethane and imidazole or 1,2,4-triazole in a superbasic medium (potassium hydroxide -dimethyl sulfoxide) was investigated using GC/MS technique. It was found that nucleophilic substitution reaction is always accompanied by elimination reactions (dehydrobromination and debromination). In addition to 1,1,2,2-tetra(azol-1-yl)ethane, 1,1,2-tri(azol-1-yl)ethenes and 1,2-di(azol-1-yl)ethenes, as well as 1,2-di(azol-1-yl)-1-bromoethenes were detected. Reaction pathway that explains the formation of all major products was proposed.