Investigation of columnar to equiaxial transition criterion and solidification conditions for Ni-based superalloy in laser powder bed fusion

Zhou, Yang1,2; Li, Xinggang2,3; Guo, Chuan2,3; Hu, Xiaogang2,3; Zhu, Qiang2,3

2023-12-05

10.1016/j.jallcom.2023.171611

JOURNAL OF ALLOYS AND COMPOUNDS   影响因子和分区

0925-8388

1873-4669

Laser powder bed fusion (L-PBF) is a pioneering additive manufacturing (AM) technology for superalloys. The study of the columnar to equiaxial transition (CET) of a superalloy in the L-PBF process is important for con-trolling the grain morphology of the superalloy and achieving the production of a superalloy with a single-crystal microstructure. This study aims to reveal the fundamental law of CET of superalloys in the L-PBF process. An algorithm was developed to successfully extend the application of the CET model to cover the solidification rate interval of the L-PBF process, and the accuracy of the model was experimentally verified. The extended CET model indicated that the critical temperature gradient from columnar epitaxial growth to equiaxial growth does not increase monotonically with increasing solidification rate but exhibits a peak. The temperature gradient at the solidification interface of the L-PBF molten pool was greater than this peak. In addition, the solidification mode of the alloy remained epitaxial after adjusting the laser power and scanning rate, because adjusting these two parameters exerted a weak effect on the temperature gradient at the solidification interface of the L-PBF molten pool. The excessively high temperature gradient of L-PBF also makes it difficult to change the solidifi-cation mode from epitaxial to equiaxial at preheating temperatures below 1000 K. Changes in the morphology of the molten pool due to the increased temperature of the deposited layer are of more concern in terms of microstructure formation. The results of this study are expected to provide guidance for designing process pa-rameters for optimizing the microstructures of superalloys fabricated using L-PBF.

Additive manufacturing Microstructure Rapid solidification Columnar to equiaxial transition

SCI ; EI

英语

通讯

National Natural Science Foundation of China["52250710160","JCYJ20210324104610029"] ; Shenzhen Science and Technology Innovation Committee["JCYJ20210324104608023","JCYJ20220818100613028"] ; null[52074157] ; null[ZDSYS20170303174 8354]

Chemistry ; Materials Science ; Metallurgy & Metallurgical Engineering

Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:001053170600001

ELSEVIER SCIENCE SA

20233214510068

3D printing ; Additives ; Microstructure ; Morphology ; Nickel alloys ; Single crystals ; Superalloys ; Thermal gradients

Metallurgy and Metallography:531 ; Nickel Alloys:548.2 ; Thermodynamics:641.1 ; Printing Equipment:745.1.1 ; Chemical Agents and Basic Industrial Chemicals:803 ; Physical Properties of Gases, Liquids and Solids:931.2 ; Crystalline Solids:933.1 ; Materials Science:951

MATERIALS SCIENCE

2-s2.0-85166949483

Web of Science

1.Harbin Inst Technol, Sch Mechatron Engn, Harbin 150001, Peoples R China
2.Southern Univ Sci & Technol, Dept Mech & Energy Engn, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Shenzhen Key Lab Addit Mfg High Performance Mat, Shenzhen 518055, Peoples R China

Zhou, Yang,Li, Xinggang,Guo, Chuan,et al. Investigation of columnar to equiaxial transition criterion and solidification conditions for Ni-based superalloy in laser powder bed fusion[J]. JOURNAL OF ALLOYS AND COMPOUNDS,2023,966.

Zhou, Yang,Li, Xinggang,Guo, Chuan,Hu, Xiaogang,&Zhu, Qiang.(2023).Investigation of columnar to equiaxial transition criterion and solidification conditions for Ni-based superalloy in laser powder bed fusion.JOURNAL OF ALLOYS AND COMPOUNDS,966.

Zhou, Yang,et al."Investigation of columnar to equiaxial transition criterion and solidification conditions for Ni-based superalloy in laser powder bed fusion".JOURNAL OF ALLOYS AND COMPOUNDS 966(2023).