Magnetic Structure and Martensite Twin-Laws of ferromagnetic Co2-Ni-Ga and Fe-Ni-Co-Al-Ta Shape Memory Alloys

Pseudoelastic, ferromagnetic Co2NiGa type high-temperature shape memory alloys (HT-SMAs) are characterized by a wide range of tunable transformation temperatures and lower processing costs compared to conventional Ni-Ti-X HT-SMAs which renders them useful for high-temperature applications in automotive and aerospace industries. Pseudoelastic FeNiCoAlTa magnetic shape memory alloys can be produced at even cheaper costs and are interesting SMAs for applications at ambient temperatures. Despite those materials' relevance for future applications, their magnetic space group, the amount of chemical ordering and martensite twin-laws have not yet been determined experimentally. In this proposal we would like to focus on magnetic structures of all phases and twin laws of martensite phases to better understand fundamental aspects and fatigue behaviour of CoNiGa and FeNiCoAlTa.