Transformational superelasticity in sputtered titanium-nickel thin films

• Published in: Scripta metallurgica et materialia Vol. 33; no. 6; pp. 989 - 995
• Main Authors: Hou, Li, Grummon, D.S.
• Format: Journal Article
• Language: English
• Published: Seoul Elsevier B.V 15.09.1995; Oxford Pergamon Press; New York, NY
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Mechanical and acoustical properties; Metals. Metallurgy; Physical properties of thin films, nonelectronic; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Nickel base alloys; Superplasticity; Phase transformations; Stress-strain relation; Experimental study; Thin films; Binary alloys; Titanium alloys; Sputtered materials; DSC; Shape memory effect; Microstructure; TEM; Transition element alloys
• ISSN: 0956-716X
• DOI: 10.1016/0956-716X(95)00311-I

The ability of sputtered thin films of titanium-nickel to exhibit classic transformational superelasticity has been clearly demonstrated for a very fine-grained, slightly nickel-rich material in the as-deposited condition. The observed dependence of the martensite-induction stress on deformation temperature was found to have the expected relationship to the transformation enthalpy. The effect may prove useful in microelectromechanical and biomechanical systems requiring structural elements with high energy storage capacity, high strength, excellent kink resistance, or nearly constant reaction-force output over large displacements. Such materials may also be useful as layers incorporated into functionally graded interfaces designed to absorb large differential strains in electronic packaging applications.