Achieving superconductivity with higher T-c in~ lightweight Al-Ti-Mg alloys: Prediction using machine learning and synthesis via high-pressure torsion process

Aluminum (Al) and titanium (Ti) are superconducting materials but their superconducting transition temperatures (T-c) are quite low as 1.20 and 0.39 K, respectively, while magnesium (Mg) never exhibits superconductivity. In this study, we explored new superconductors with higher T-c & nbsp;in the Al-Mg-Ti ternary system, along with the prediction using machine learning. High-pressure torsion (HPT) is utilized to produce the superconducting states. While performing AC magnetization measurements, we found, for the first time, superconducting states with T-c & nbsp;= 4.0 and 7.3 K for a composition of Al:Ti = 1:2. The magnetic anomalies appeared more sharply when the sample was processed by HPT at 573 K than at room temperature, and the anomalies exhibited DC magnetic field dependence characteristic of superconductivity. Magnetic anomalies also appeared at similar to 55 & nbsp;and similar to 93 K, being supported by the prediction using the machine learning for the Al-Ti-O system, and this suggests that Al-Ti oxides play an important role in the advent of such anomalies but that the addition of Mg could be less effective.& nbsp;& nbsp;Published under an exclusive license by AIP Publishing.