Fe–Pd–(Ga, Mn) ferromagnetic shape memory ribbons: Interplay between surface properties, corrosion, cell adhesion, magnetic response and martensitic transformation

Rapidly solidified Fe–Pd-based ferromagnetic shape memory alloy ribbons, modified with Mn or Ga additions, were produced and subjected to post-solidification heat treatments of varying duration to investigate the interplay between composition, surface characteristics, and functional properties. Surface morphology and wettability were evaluated alongside corrosion behavior, magnetic response, martensitic transformation, and in vitro cell adhesion. Corrosion performance was assessed through immersion and electrochemical techniques, providing insight into degradation kinetics. The results reveal a complex coupling between surface properties, corrosion resistance, and cell adhesion responses. Binary Fe–Pd ribbons exhibit moderately rough, homogeneous surfaces with stable Wenzel-type wetting, but limited electrochemical stability due to the reactivity of iron. Mn-containing ribbons display heterogeneous surface features and locally poor wettability after short heat treatments, leading to reduced corrosion resistance and degradation of magnetic and martensitic properties; nevertheless, they support favorable fibroblast adhesion. Prolonged annealing improves surface uniformity and wettability, while maintaining moderate corrosion resistance and good cell adhesion. Ga-containing ribbons show highly nonuniform topography combined with good hydrophilicity and the highest corrosion resistance, attributed to the formation of stable Ga–O protective products. Although corrosion effects are mitigated, partial suppression of magnetic and martensitic responses is observed. The findings highlight the potential of Fe–Pd-based ferromagnetic shape memory alloy ribbons as degradable biomedical substrates.