Comparison of predictions of microsegregation in the Ni–Cr–Mo system to experimental measurements

Experimental measurements of microsegregation in six Ni–Cr–Mo alloys are compared to closed system simulations. The calculations accurately predict the segregation of molybdenum, but underpredict the primary solid fraction and tend to overpredict chromium segregation at late stages of solidification. Analysis of the data suggests that the difference between the calculations and the measurements may be caused by a delay in the nucleation of the secondary phases. Upon adjusting for this delay and using the experimentally determined partition coefficients, the model better predicts the phase fractions and segregation in the alloys.