Transient nucleation in selective laser melting of Zr-based bulk metallic glass

Research output: Contribution to journalArticle

Abstract

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.

Details

Authors
Organisations
External organisations
  • Uppsala University
  • Luleå University of Technology
  • Malmö University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Materials Engineering

Keywords

  • Additive manufacturing, Classical nucleation theory, Crystallization, Metallic glass, Selective laser melting, Transient nucleation
Original languageEnglish
Article number108958
JournalMaterials and Design
Volume195
Publication statusPublished - 2020
Publication categoryResearch
Peer-reviewedYes