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Highlights: [•] A physically based material model is coupled with a model for growth and coarsening. [•] The model for precipitate evolution accounts for nucleation, growth and coarsening. [•] Compression tests for solution annealed, half-aged and fully-aged material. [•] The material model shows good agreement with experimental measurements. [•] The model can be used in thermo-mechanical simulation of the ageing process in IN718. [ABSTRACT FROM AUTHOR]

The crystallization rate during selective laser melting (SLM) of bulk metallic glasses (BMG) is a critical factor in maintaining the material's amorphous structure. To increase the understanding of the interplay between the SLM process and the crystallization behavior of BMGs, a numerical model based on the classical nucleation theory has been developed that accounts for the rapid temperature changes associated with SLM. The model is applied to SLM of a Zr-based BMG and it is shown that the transient effects, accounted for by the model, reduce the nucleation rate by up to 15 orders of magnitude below the steady-state nucleation rate on cooling, resulting in less nuclei during the build process. The capability of the proposed modelling approach is demonstrated by comparing the resulting crystalline volume fraction to experimental findings. The agreement between model predictions and the experimental results clearly suggests that transient nucleation effects must be accounted for when considering the crystallization rate during SLM processing of BMGs. Unlabelled Image • Crystallization in SLM processing of AMZ4 is predicted using a transient nucleation model based on CNT. • The nucleation rate is shown to depend on the heating/cooling rate of the temperature cycles in SLM. • A diminishing volume fraction is observed at laser powers below 80 W, in agreement with XRD analysis of SLM processed AMZ4. • The results suggest that transient nucleation effects play a critical role in promoting glass formation in SLM. [ABSTRACT FROM AUTHOR]