Junkang Wu , Yang Huang , Yun Tan , Jialiao Zhou , Jian Yao , Liming Tan , Zi Wang , Lan Huang , Feng Liu
{"title":"颗粒尺寸依赖性凝固不均匀性:气雾化镍基高温合金粉末的模拟与实验解耦","authors":"Junkang Wu , Yang Huang , Yun Tan , Jialiao Zhou , Jian Yao , Liming Tan , Zi Wang , Lan Huang , Feng Liu","doi":"10.1016/j.powtec.2025.121658","DOIUrl":null,"url":null,"abstract":"<div><div>The microstructural uniformity of nickel-based superalloy powders for additive manufacturing has been recognized as a critical factor influencing the performance of built components. However, the particle-size-dependent solidification mechanisms during gas atomization remain poorly understood. In this study, the temperature fields and solidification histories of droplets with varying diameters were reconstructed through coupled thermo-fluid dynamics simulations. Combined with multi-scale characterization techniques, the effects of particle size on solidification structure, elemental segregation behavior, and grain structure were systematically investigated. The results revealed that cooling rate decreased with increasing particle size. Fine powders exhibited a cellular solidification structure due to rapid cooling, whereas coarse powders developed coarser dendritic morphologies, with the secondary dendrite arm spacing following a power-law relationship with particle size. In terms of solute segregation, positive segregation of Nb and Ti was observed in larger particles under near-equilibrium diffusion conditions, while Mo exhibited negative segregation due to diffusion limitations. Rapid solidification in smaller particles led to solute trapping and the formation of non-equilibrium microstructures. Grain structure analysis showed that smaller particles contained fewer but larger grains, whereas larger particles exhibited a multi-scale microstructure composed of both equiaxed and columnar dendrites. This work elucidated the size-dependent solidification pathways and microstructural evolution in gas-atomized nickel-based superalloy powders, providing a theoretical foundation for the tailored design and microstructural control of nickel-based superalloy powders for high-performance additive manufacturing applications.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"468 ","pages":"Article 121658"},"PeriodicalIF":4.6000,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Particle size-dependent solidification heterogeneity: Simulation and experimental decoupling of gas-atomized Ni-based superalloy powders\",\"authors\":\"Junkang Wu , Yang Huang , Yun Tan , Jialiao Zhou , Jian Yao , Liming Tan , Zi Wang , Lan Huang , Feng Liu\",\"doi\":\"10.1016/j.powtec.2025.121658\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The microstructural uniformity of nickel-based superalloy powders for additive manufacturing has been recognized as a critical factor influencing the performance of built components. However, the particle-size-dependent solidification mechanisms during gas atomization remain poorly understood. In this study, the temperature fields and solidification histories of droplets with varying diameters were reconstructed through coupled thermo-fluid dynamics simulations. Combined with multi-scale characterization techniques, the effects of particle size on solidification structure, elemental segregation behavior, and grain structure were systematically investigated. The results revealed that cooling rate decreased with increasing particle size. Fine powders exhibited a cellular solidification structure due to rapid cooling, whereas coarse powders developed coarser dendritic morphologies, with the secondary dendrite arm spacing following a power-law relationship with particle size. In terms of solute segregation, positive segregation of Nb and Ti was observed in larger particles under near-equilibrium diffusion conditions, while Mo exhibited negative segregation due to diffusion limitations. Rapid solidification in smaller particles led to solute trapping and the formation of non-equilibrium microstructures. Grain structure analysis showed that smaller particles contained fewer but larger grains, whereas larger particles exhibited a multi-scale microstructure composed of both equiaxed and columnar dendrites. This work elucidated the size-dependent solidification pathways and microstructural evolution in gas-atomized nickel-based superalloy powders, providing a theoretical foundation for the tailored design and microstructural control of nickel-based superalloy powders for high-performance additive manufacturing applications.</div></div>\",\"PeriodicalId\":407,\"journal\":{\"name\":\"Powder Technology\",\"volume\":\"468 \",\"pages\":\"Article 121658\"},\"PeriodicalIF\":4.6000,\"publicationDate\":\"2025-09-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Powder Technology\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0032591025010538\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENGINEERING, CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Powder Technology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0032591025010538","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
Particle size-dependent solidification heterogeneity: Simulation and experimental decoupling of gas-atomized Ni-based superalloy powders
The microstructural uniformity of nickel-based superalloy powders for additive manufacturing has been recognized as a critical factor influencing the performance of built components. However, the particle-size-dependent solidification mechanisms during gas atomization remain poorly understood. In this study, the temperature fields and solidification histories of droplets with varying diameters were reconstructed through coupled thermo-fluid dynamics simulations. Combined with multi-scale characterization techniques, the effects of particle size on solidification structure, elemental segregation behavior, and grain structure were systematically investigated. The results revealed that cooling rate decreased with increasing particle size. Fine powders exhibited a cellular solidification structure due to rapid cooling, whereas coarse powders developed coarser dendritic morphologies, with the secondary dendrite arm spacing following a power-law relationship with particle size. In terms of solute segregation, positive segregation of Nb and Ti was observed in larger particles under near-equilibrium diffusion conditions, while Mo exhibited negative segregation due to diffusion limitations. Rapid solidification in smaller particles led to solute trapping and the formation of non-equilibrium microstructures. Grain structure analysis showed that smaller particles contained fewer but larger grains, whereas larger particles exhibited a multi-scale microstructure composed of both equiaxed and columnar dendrites. This work elucidated the size-dependent solidification pathways and microstructural evolution in gas-atomized nickel-based superalloy powders, providing a theoretical foundation for the tailored design and microstructural control of nickel-based superalloy powders for high-performance additive manufacturing applications.
期刊介绍:
Powder Technology is an International Journal on the Science and Technology of Wet and Dry Particulate Systems. Powder Technology publishes papers on all aspects of the formation of particles and their characterisation and on the study of systems containing particulate solids. No limitation is imposed on the size of the particles, which may range from nanometre scale, as in pigments or aerosols, to that of mined or quarried materials. The following list of topics is not intended to be comprehensive, but rather to indicate typical subjects which fall within the scope of the journal's interests:
Formation and synthesis of particles by precipitation and other methods.
Modification of particles by agglomeration, coating, comminution and attrition.
Characterisation of the size, shape, surface area, pore structure and strength of particles and agglomerates (including the origins and effects of inter particle forces).
Packing, failure, flow and permeability of assemblies of particles.
Particle-particle interactions and suspension rheology.
Handling and processing operations such as slurry flow, fluidization, pneumatic conveying.
Interactions between particles and their environment, including delivery of particulate products to the body.
Applications of particle technology in production of pharmaceuticals, chemicals, foods, pigments, structural, and functional materials and in environmental and energy related matters.
For materials-oriented contributions we are looking for articles revealing the effect of particle/powder characteristics (size, morphology and composition, in that order) on material performance or functionality and, ideally, comparison to any industrial standard.