Additive manufacturing of Nickel-Titanium shape memory alloys with help of laser metal deposition

• Applicants: Dr.-Ing. Andrey Gumenyuk; Dr.-Ing. Jürgen Olbricht
• Subject Area: Joining and Separation Technology ; Metallurgical, Thermal and Thermomechanical Treatment of Materials
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 523635507

In the applied research, NiTi-alloys are additively processed by laser metal deposition (LMD). According to their special property of shape memory (shape memory effects, SME) NiTi are interesting alloy systems and are used in many areas. Examples include damping elements in the automotive sector, locknuts in aerospace engineering and implants in medical technology. The SME and the pseudoelastic behavior of NiTi-alloys are due to the reversible martensite-austenite phase transformation, which can be triggered both thermally and mechanically. The goal of the research is to develop a LMD-process using a binary and at room temperature pseudoelastic NiTi-alloy with 50.8 at.% Ni. In addition to the production of a homogenous elementary powder mixture, the LMD-process will be developed and the additive-manufactured samples are analyzed for grain structure, phase composition and the thermal as well as the mechanical phase transformation behavior. The dependence between powder composition and process parameters and the resulting microstructure and properties are to be determined. Furthermore, the project includes the development of suitable after heat treatments to optimize the shape memory properties of the additively produced NiTi-alloys. For the first time, the applied research project will develop production routines, machining approaches as well as analytical and process chains for additive manufacturing of components made of NiTi-alloys as a basis for further application-oriented researches.

• DFG Programme: Research Grants
• Co-Investigators: Professor Dr.-Ing. Michael Rethmeier; Professorin Dr.-Ing. Birgit Skrotzki