Simulation and analysis of $\gamma$-Ni cellular growth during laser powder deposition of Ni-based superalloys

Abstract

Cellular or dendritic microstructures that result as a function of additive manufacturing solidification conditions in a Ni-based melt pool are simulated in the present work using three-dimensional phase-field simulations. A macroscopic thermal model is used to obtain the temperature gradient $G$ and the solidification velocity $V$ which are provided as inputs to the phase-field model. We extract the cell spacings, cell core compositions, and cell tip as well as mushy zone temperatures from the simulated microstructures as a function of $V$. Cell spacings are compared with different scaling laws that correlate to the solidification conditions and approximated by $G^{-m}{V}^{-n}$. Cell core compositions are compared with the analytical solutions of a dendrite growth theory and found to be in good agreement. Through analysis of the mushy zone, we extract a characteristic bridging plane, where the primary $\gamma$ phase coalesces across the intercellular liquid channels at a $\gamma$ fraction between 0.6 and 0.7. The temperature and the $\gamma$ fraction in this plane are found to decrease with increasing $V$. The simulated microstructural features are significant as they can be used as inputs for the simulation of subsequent heat treatment processes.

arXiv commentAccepted for Publication in Computational Materials Science on December 16, 2017

References in corpus (5)

• Phase-Field Formulation for Quantitative Modeling of Alloy Solidification
• Quantitative Phase Field Model of Alloy Solidification
• Application of Finite Element, Phase-field, and CALPHAD-based Methods to Additive Manufacturing of Ni-based Superalloys
• On the primary spacing and microsegregation of cellular dendrites in laser deposited Ni-Nb alloys
• Formation of Nb-rich droplets in laser deposited Ni-matrix microstructures

Cited by in corpus (14)

• Finite Interface Dissipation Phase Field Modeling of Ni-Nb under Additive Manufacturing Conditions
• Strongly out-of-equilibrium columnar solidification during the Laser Powder-Bed Fusion additive manufacturing process
• Microstructural Pattern Formation during Far-from-Equilibrium Alloy Solidification
• Predictive modeling of solidification during laser additive manufacturing of nickel superalloys: Recent developments, future directions
• Formation of Nb-rich droplets in laser deposited Ni-matrix microstructures
• Uncertainty Analysis of Microsegregation during Laser Powder Bed Fusion
• Simulation of temperature, stress and microstructure fields during laser deposition of Ti-6Al-4V
• Tusas: A fully implicit parallel approach for coupled phase-field equations
• Time series forecasting of multiphase microstructure evolution using deep learning
• Orientation selection in alloy dendritic evolution during melt-pool solidification
• Exploring large language models for microstructure evolution in materials
• Effects of isotherm patterns on cellular interface morphologies of melt pool origin
• A multi-grid Cellular Automaton model for simulating dendrite growth and its application in additive manufacturing
• Quantitative phase field modeling of solute trapping and continuous growth kinetics in rapid solidification