Suspended droplet alloying: A new method for combinatorial alloy synthesis; nitinol-based alloys as an example

Abstract

A new combinatorial alloy synthesis method (suspended droplet alloying) has been developed as a high-throughput approach for alloy discovery. The method is based on using a laser to melt elemental or alloyed wires fed at a controlled rate to achieve a specific chemistry. In this study, the metallurgical characteristics of alloy buttons created using this technique were assessed for TiNi-based shape memory alloy buttons deposited using pure Ni, Ti, and Cu wires. The microstructural and chemical inhomogeneity was assessed using quantitative electron microscopy and X-ray diffraction. Furthermore, the phase transformation temperatures of the coupons have been compared to cast and heat-treated (reference) samples. In general, the samples displayed a limited local deviation from the target chemistry (±1 wt.%), while displaying a fairly homogeneous microstructure with the expected phase distribution. Post-process homogenisation heat treatments enhanced the phase transformation response, approaching the response obtained from the reference samples.

Pt-Ni Nanoalloys for H2 Generation from Hydrous Hydrazine

“…In the past reports, many transition metal nano-catalysts have been synthesized by co-precipitation [51], chemical reduction, combustion synthesis [52], galvanic displacement [53], impregnation [54], and alloying [55]. Among them, alloying is an effective strategy to improve catalytic activity and hydrogen selectivity [55]. Fixing the catalyst nanoparticles on the basic carrier can not only improve the durability of the catalyst, but also improve the selectivity of hydrogen [56].…”

Insight into the Activity and Selectivity of Nanostructured Copper Titanates during Electrochemical Conversion of CO2 at Neutral pH via In Situ X-ray Absorption Spectroscopy

“…A two-electrode configuration was employed for cathodic corrosion synthesis, as described previously, using LabVIEW/National Instruments hardware and a homebuilt power amplifier. ,,, NTO and Cu:NTO nanowires were prepared by applying a square waveform oscillating between 0 and −10 V at 100 Hz across the working electrode (WE) (Ti wire of 0.25 mm diameter and Cu 19 Ti 81 alloy, respectively) and a high-surface area Pt flag used as a counter electrode (CE), submerged in 10 M NaOH (Merck, ≥99%) solution . The Cu 19 Ti 81 alloy was prepared via suspended droplet alloying , (see the Supporting Information for experimental details). CuO nanoparticles were prepared by applying a square waveform oscillating between +4 and −4 V at 100 Hz across the working electrode (Cu wire of 0.41 mm) in 90% saturated CaCl 2 (Merck, anhydrous ≥93%).…”

Effect of Stoichiometry on Shape Memory Properties of Ti-Ni-Hf-Cu-Nb Shape Memory Alloys Manufactured by Suspended Droplet Alloying

“…Hence, we developed a rapid alloying system, Suspended Droplet Alloying (SDA), to conquer the problem and systematically study the influence of alloying elements on the MT of Ti-Ni-based SMAs. The specifics of this technique are detailed in a previously published study [25]. Here, we proposed using Hf to improve the M s while using Nb and Cu to adjust the hysteresis and thermal stability of Ti-Ni-based SMAs by prompting nucleation, forming various precipitates and altering the matrix composition.…”