Composition–Structure–Function Diagrams of Ti–Ni–Au Thin Film Shape Memory Alloys

Abstract

Ti-Ni-Au thin film materials libraries were prepared from multilayer precursors by combinatorial sputtering. The materials libraries were annealed at 500, 600, and 700 °C for 1 h and then characterized by high-throughput methods to investigate the relations between composition, structure and functional properties. The identified relations were visualized in functional phase diagrams. The goal is to identify composition regions that are suitable as high temperature shape memory alloys. Phase transforming compositions were identified by electrical resistance measured during thermal cycles in the range of -20 and 250 °C. Three phase transformation paths were confirmed: (1) B2-R, (2) B2-R-B19', and (3) B2-B19. For the materials library annealed at 500 °C only the B2-R transformation was observed. For the materials libraries annealed at 600 and 700 °C, all transformation paths were observed. High transformation temperatures (M(s) ≈ 100 °C) were only obtained by annealing at 600 or 700 °C, and with compositions of Ti ≈ 50 at. % and Au > 20 at. %. This is the composition range that undergoes B2-B19 transformation. The phase transformation behaviors were explained according to the compositional and annealing temperature dependence of phase/structure formation, as revealed by X-ray diffraction analysis of the materials libraries.

Crystallography companion agent for high-throughput materials discovery

“…This is accomplished without pre-labelled data, is robust against many sources of complexity in diffraction, and is extendable to other forms of characterization that can be accurately simulated (e.g., spectroscopy). This complements recent advancements in automation [1,2,[15][16][17][18][19][20][21] and autonomous experimentation [1][2][3], and marks a crucial step in the acceleration of materials discovery.…”

Nanostructured Ti–Ta thin films synthesized by combinatorial glancing angle sputter deposition

“…Using a combinatorial approach together with high-throughput characterization methods lead to faster assessment of materials due to well-comparable samples produced at the same time and under identical conditions. However, the thin-film combinatorial approach has so far mainly been reported for investigations of compact and dense thin films [3,14,15,[47][48][49]. The fabrication of materials libraries with distinct nanostructured morphologies was rarely reported [50].…”