Fabrication, microstructure and stress effects in sputtered TiNi thin films

Sputtered thin films of equiatomic TiNi and TiNiX ternary alloys have excellent mechanical properties and exhibit robust shape-memory and transformational superelasticity. Furthermore, the energetic nature of the sputter deposition process allows the creation of highly refined microstructures that are difficult to achieve by melt-solidification. The present paper will present recent work on the relationship between processing, microstructure and properties of binary TiNi thin films, focusing primarily on residual stresses, kinetics of stress-relaxation and crystallization, and fine grain sizes achievable using hot-substrate direct crystallization.