Selective conversion of NiTi to NiTiZr high temperature shape memory alloy

High temperature shape memory alloys (HTSMA) promise to overcome persistent challenges faced with conventional alloys, including actively operating at elevated temperatures (+100^oC) and increasing actuation frequency. However the fabrication of HTSMA’s has proven to be challenging due to the limited workability, compositional sensitivity, and high cost of alloying elements. The current work implements the multiple memory material technology to selectively convert regions of a binary NiTi alloy to a ternary NiTiZr high temperature SMA. Thermal and mechanical testing confirmed the formation of a localized HTSMA while the surrounding material maintained its original properties.  This novel method has the potential to enable new dimensional control for the design and fabrication of SMA devices requiring high temperature properties while maintaining affordability.