Numerical Analysis Nucleation and Growth Conditions of Single-Crystallinity Control during Laser Surface Modification of Ni-Based Single-Crystal Superalloy Part I: Thermal and Chemical Determinants

Abstract:

Nucleation and growth conditions of single-crystallinity control are convincingly elaborated by multi-scale mathematical modeling of heat and mass transport to totally abate undesirable weld defects, e.g. disoriented crystal and hot cracking inside molten pool of nonequilibrium crystallization, in order to illustrate the usefulness of predictive capability through theory and experiment procedures. Crystal growth is complicated by crystallinity-dependent thermal and chemical driving forces in front of dendrite tip during viable laser surface modification of Ni-based single-crystal superalloy. These two thermal metallurgical determinants play crucial role in crack-insusceptible columnar crystal growth, which is favorably oriented throughout weld depth. There is particular challenge in complete elimination of disoriented crystal, i.e. stray grain formation, for acceptable surface quality. Conservative (001)/[100] crystalline orientation is desired to diminish Al concentration and supersaturation, and morphologically satisfy epitaxial growth kinetics to successfully lessen central cracking with satisfactory variability of laser power and welding speed. Comparatively, (001)/[110] crystalline orientation is disadvantageous to asymmetrically augment Al concentration and supersaturation and aggressively increase interface instability, microstructure heterogeneity and hot cracking vulnerability along disoriented crystal boundaries. Disoriented crystal is increasingly withstood if the Al concentration and supersaturation in front of dendrite tip are low enough and crack-unsusceptible part is relatively large enough in case of attractive (001)/[100] crystalline orientation with optimal range of heat input to ameliorate microstructure homogeneity. Crystalline orientation region varies with diverse welding configurations, and epitaxy across solid/liquid interface is also sensitive to heat input of laser processing, which necessitate high efficient welding conditions optimization. Considerable effort is made to distinguish diffusion-driven crystal growth between a series of combinations of multiple welding conditions, such as critical welding configuration and heat input. Metallographically, the morphologies of crystal growth and hot cracking are experimentally observed to consistently support kinetics calculation result and well explain correlation between solidification behavior and crystal growth.

• Periodical: Solid State Phenomena (Volume 331)
• Pages: 37-46
• DOI: https://doi.org/10.4028/p-46h9g5
• Online since: April 2022
• Authors: Zhi Guo Gao*
• Keywords: Crystal Growth, Crystalline Orientation, Hot Cracking, Laser Surface Modification, Microstructure Control, Multi-Scale Modeling

References

[1] Y.M. Zhang, M. Hida. Influence of WC addition on microstructures of laser-melted Ni-based alloy coating. Journal of Materials Engineering and Performance,11(2002),667-674.

DOI: 10.1361/105994902770343674

[2] Mariia Rashkovets, Aelita Nikulina. Microstructure and phase composition of Ni-based alloy obtained by high-speed direct laser deposition. Journal of Materials Engineering and Performance, 27(2018),6398-6406.

DOI: 10.1007/s11665-018-3722-y

[3] C.Y. Su, C.P. Chou. Plasma-transferred arc repair welding of the nickel-based superalloy IN738LC. Journal of Materials Engineering and Performance,6(1997),619-627.

DOI: 10.1007/s11665-997-0055-7

[4] M. Sathishkumar, Y. J. Bhakat. Investigation of double-pulsed gas metal arc welding technique to preclude carbide precipitates in aerospace grade Hastelloy X. Journal of Materials Engineering and Perfoemance,30(2021),661-684.

DOI: 10.1007/s11665-020-05360-1

[5] Bernd Baufeld. Mechanical properties of Inconel 718 parts manufactured by shaped metal deposition (SMD). Journal of Materials Engineering and Performance,21(2012),1416-1421.

DOI: 10.1007/s11665-011-0009-y

[6] S. Sujai, K.D. Ramkumar. Microstructure and mechanical characterization of Incoloy 925 welds in the as-welded and direct aged conditions. Journal of Materials Engineering and Performance, 28(2019),1563-1580.

DOI: 10.1007/s11665-019-03960-0

[7] Kwai S. Chan. Mechanism-based models for predicting the microstructure and stress-strain response of additively manufactured superalloy 718 plus. Journal of Materials Engineering and Performance,29(2020),2035-2045.

DOI: 10.1007/s11665-020-04678-0

[8] Giulio Marchese, Eleonora Atzeni. Microstructure and residual stress of laser powder bed fused Inconel 718 under heat treatments. Journal of Materials Engineering and Performance,30(2021), 565-574.

DOI: 10.1007/s11665-020-05338-z

[9] Adelajda Polkowska, Wojciech Polkowski. Microstructure and hardness evolution in Haynes 282 nickel-based superalloy during multi-variant aging heat treatment. Journal of Materials Engineering and Performance,28(2019),3844-3851.

DOI: 10.1007/s11665-019-3886-0

[10] Cosimo Monti, Alessandro Giorgetti. On the effect of the rejuvenation treatment on mechanical and microstructural properties of IN738 superalloy. Journal of Materials Engineering and Performance,26(2017),2244-2256.

DOI: 10.1007/s11665-017-2646-2

[11] I. Guzman, E. Granda. Particle size of gamma prime as a result of vacuum heat treatment of Inconel 738 superalloy. Journal of Materials Engineering and Performance, 22(2013), 1143-1148.

DOI: 10.1007/s11665-012-0385-y

[12] Fan Yang, Jiang Wang. Microstructure and mechanical properties of Ni-based superalloy K418 produced by the continuous unidirectional solidification process. Journal of Materials Engineering and Performance,28(2019),6483-6491.

DOI: 10.1007/s11665-019-04385-5

[13] Y.F. Han, Y.M. Wang. Microstructure/mechanical property relationship in a DS cast Ni3Al- based alloy. Journal of Materials Engineering and Performance,2(1993),589-596.

DOI: 10.1007/bf02661745

[14] Amrita Basak, S.H. Raghu. Microstructures and microhardness properties of CMSX-4 additively fabricated through scanning laser epitaxy (SLE). Journal of Materials Engineering and Performance, 26(2017),5877-5884.

DOI: 10.1007/s11665-017-3008-9

[15] Camila P. Alvaraes, Soraia S. Sandes. Microstructural characterization of Inconel 625 nickel- based alloy weld cladding obtained by electroslag welding process. Journal of Materials Engineering and Performance,29(2020),3004-3015.

DOI: 10.1007/s11665-020-04861-3

[16] D. Szeliga, K. Kubiak. Modeling of directional solidification of columnar grain structure in CMSX-4 nickel-based superalloy castings. Journal of Materials Engineering and Performance, 23(2014), 1088-1095.

DOI: 10.1007/s11665-013-0820-8

[17] X. Wang, P.W. Liu. Investigation on microsegregation of IN718 alloy during additive manufacturing via integrated phase-field and finite-element modeling. Journal of Materials Engineering and Performance,28(2019),657-665.

DOI: 10.1007/s11665-018-3620-3

[18] Zhiguo Gao. Numerical analysis of stray grain formation during laser welding nickel-based single-crystal superalloy part I: columnar/equiaxed morphology transition. Journal of Physics: Conference Series,1888(2021),012004.

DOI: 10.1088/1742-6596/1888/1/012004

[19] Zhiguo Gao. Numerical analysis of microstructure anomalies during laser welding nickel-based single-crystal superalloy part III: amelioration of solidification behavior. Materials Science Forum, 1041(2021),47-56.

DOI: 10.4028/www.scientific.net/msf.1041.47