Abstract
Gaussian process regression machine learning with a physically-informed kernel is used to model the phase compositions of nickel-base superalloys. The model delivers good predictions for laboratory and commercial superalloys, with R-2 > 0.8 for all but two components of each of the gamma and gamma' phases, and R-2 = 0.924 (RMSE = 0.063) for the gamma' fraction. For four benchmark SX-series alloys the methodology predicts the gamma' phase composition with RMSE = 0.006 and the fraction with RMSE = 0.020, superior to the 0.007 and 0.021 respectively from CALPHAD. Furthermore, unlike CALPHAD Gaussian process regression quantifies the uncertainty in predictions, and can be retrained as new data becomes available.