TY - JOUR

T1 - Additive manufacturing of magnesium alloy using uniform droplet spraying: modeling of microstructure evolution

AU - Jaffar, Syed Murtaza

AU - Kostoglou, Nikolaos

AU - Fukuda, Hiroki

AU - Rebholz, Claus

AU - Ando, Teiichi

AU - Liao, Yiliang

AU - Doumanidis, Charalabos C.

N1 - Publisher Copyright: © 2021, The Author(s), under exclusive licence to The Materials Research Society.

PY - 2021/6

Y1 - 2021/6

N2 - Abstract: In this study a material model is developed to predict the solidification microstructure of an additive-manufactured, fully dense magnesium (Mg) alloy using uniform droplet spraying (UDS). Specifically, the crystallite size distribution is simulated by a solidification model, consisting of a nucleation/fragmentation and a constrained growth description, calibrated via microstructural data from a single droplet splat. This is enabled by a semi-analytical thermal modeling framework, based on the superposition of moving Green’s and Rosenthal functions for the temperature field generated by a Gaussian source distribution. The model is implemented for layered ellipsoidal deposit sections on planar substrates by multi-pass spraying, and its predictions are validated against measured crystal sizes by image analysis of experimental micrographs of a Mg 97ZnY 2 alloy, to an error margin of ± 15%. The computationally efficient simulation provides insights to the deposit microstructure, and is intended as a process observer in a closed-loop, adaptive control scheme based on infrared temperature measurements. Graphic abstract: [Figure not available: see fulltext.]

AB - Abstract: In this study a material model is developed to predict the solidification microstructure of an additive-manufactured, fully dense magnesium (Mg) alloy using uniform droplet spraying (UDS). Specifically, the crystallite size distribution is simulated by a solidification model, consisting of a nucleation/fragmentation and a constrained growth description, calibrated via microstructural data from a single droplet splat. This is enabled by a semi-analytical thermal modeling framework, based on the superposition of moving Green’s and Rosenthal functions for the temperature field generated by a Gaussian source distribution. The model is implemented for layered ellipsoidal deposit sections on planar substrates by multi-pass spraying, and its predictions are validated against measured crystal sizes by image analysis of experimental micrographs of a Mg 97ZnY 2 alloy, to an error margin of ± 15%. The computationally efficient simulation provides insights to the deposit microstructure, and is intended as a process observer in a closed-loop, adaptive control scheme based on infrared temperature measurements. Graphic abstract: [Figure not available: see fulltext.]

KW - Additive manufacturing

KW - Mg

KW - Microstructure

KW - Modeling

KW - Spray deposition

UR - http://www.scopus.com/inward/record.url?scp=85101751496&partnerID=8YFLogxK

U2 - 10.1557/s43580-021-00028-x

DO - 10.1557/s43580-021-00028-x

M3 - Article

VL - 6

SP - 391

EP - 403

JO - MRS Advances

JF - MRS Advances

SN - 2059-8521

IS - 15

ER -