Affiliations: Centre for Implantable Technology and Sensors, ITIS d. o. o. Ljubljana, Ljubljana, Republic of Slovenia | Department of Materials and Metallurgy, Faculty of Natural Sciences and Engineering, University of Ljubljana, Ljubljana, Republic of Slovenia | Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Republic of Slovenia
Note: [] Address for correspondence: Janez Rozman, Centre for Implantable Technology and Sensors, ITIS d. o. o. Ljubljana, Lepi pot 11, 1000 Ljubljana, Republic of Slovenia. Tel.: +386 41 415 268; E-mail: [email protected]
Abstract: OBJECTIVE: The objective of this study was to investigate the structural properties of a cold-rolled platinum foil used to manufacture multi-electrode spiral nerve cuffs. METHODS: To attain this objective, 0.03-mm-thick cold-rolled platinum foil strips with 99.99 wt% purity were used. The resistivity measurements were made using a 4-point probe technique in which the strips were subjected to dynamic annealing in an argon atmosphere. The stored energy of platinum was recorded in an argon atmosphere using differential scanning calorimetry (DSC). Finally, the microstructure of the strips was investigated by optical microscopy. RESULTS: In the resistivity measurements, a small change is observed at ~280°C. This change could be explained as the partial recovery elicited by the decrease of dislocation density. Above 500°C, a significant decrease in resistivity was recorded, and the decrease reached a maximum at ~750°C. These results are consistent with the recrystallization trend detected in DSC, namely the DSC measurement detected very weak heat release during recrystallization, which was actually accumulated during the cold-working. This exothermal peak occurred in the temperature range 380–800°C.
