Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys

Publikationen: KonferenzbeitragPaper(peer-reviewed)

Standard

Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys. / Zhang, Zhao; Wu, Menghuai; Liu, Xiaoshan et al.
2023. Beitrag in MCWASP XVI IOP Conf. Series: Materials Science and Engineering.

Publikationen: KonferenzbeitragPaper(peer-reviewed)

Vancouver

Zhang Z, Wu M, Liu X, Song M, Ludwig A, Kharicha A. Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys. 2023. Beitrag in MCWASP XVI IOP Conf. Series: Materials Science and Engineering. doi: 10.1088/1757-899X/1281/1/012059

Author

Zhang, Zhao ; Wu, Menghuai ; Liu, Xiaoshan et al. / Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys. Beitrag in MCWASP XVI IOP Conf. Series: Materials Science and Engineering.11 S.

Bibtex - Download

@conference{663f889adc024791b53988ac002560ca,
title = "Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys",
abstract = "Freckles, a significant issue encountered during the directional solidification of superal-loys, are recognised by a trail of equiaxed grains parallel to the direction of gravity accompanied bylocal eutectic enrichment. In the current study, a mixed-columnar-equiaxed multiphase volume-av-erage solidification model was employed to study the formation of freckles in superalloy casting.Fragments produced via flow-driven and capillary-driven fragmentation mechanisms are consideredas the source of spurious grains. The transport and the growth/remelting of the fragments are consid-ered. According to the simulation results, some segregation channels develop at the corners of thecasting. Flow-driven fragments are produced in/around the segregation channels, whereas capillary-driven fragments are produced at a certain depth of the mushy zone across the entire section of thecasting. The fragmentation rate caused by the flow-driven mechanism is several orders of magnitudelarger than that caused by the capillary-driven mechanism, i.e. the flow-driven fragmentation mech-anism is dominant for the currently investigated sample. After the solidification process, four frecklesformed at the casting corners on the shadowed side, whereas it was freckle-free on the bright side.",
keywords = "formation of spurious grains, formation of spurious grains and freck- les, spurious grains and freck- les, directional solidification, superalloys",
author = "Zhao Zhang and Menghuai Wu and Xiaoshan Liu and Min Song and Andreas Ludwig and Abdellah Kharicha",
note = "This work was financially supported by the Austrian Science Fund in the framework of the FWF-NKFIN joint project (FWF, I4278-N36).; MCWASP XVI IOP Conf. Series: Materials Science and Engineering ; Conference date: 18-06-2023 Through 23-06-2023",
year = "2023",
doi = "10.1088/1757-899X/1281/1/012059",
language = "English",

}

RIS (suitable for import to EndNote) - Download

TY - CONF

T1 - Numerical study on the formation of spurious grains and freckles during the directional solidification of superalloys

AU - Zhang, Zhao

AU - Wu, Menghuai

AU - Liu, Xiaoshan

AU - Song, Min

AU - Ludwig, Andreas

AU - Kharicha, Abdellah

N1 - This work was financially supported by the Austrian Science Fund in the framework of the FWF-NKFIN joint project (FWF, I4278-N36).

PY - 2023

Y1 - 2023

N2 - Freckles, a significant issue encountered during the directional solidification of superal-loys, are recognised by a trail of equiaxed grains parallel to the direction of gravity accompanied bylocal eutectic enrichment. In the current study, a mixed-columnar-equiaxed multiphase volume-av-erage solidification model was employed to study the formation of freckles in superalloy casting.Fragments produced via flow-driven and capillary-driven fragmentation mechanisms are consideredas the source of spurious grains. The transport and the growth/remelting of the fragments are consid-ered. According to the simulation results, some segregation channels develop at the corners of thecasting. Flow-driven fragments are produced in/around the segregation channels, whereas capillary-driven fragments are produced at a certain depth of the mushy zone across the entire section of thecasting. The fragmentation rate caused by the flow-driven mechanism is several orders of magnitudelarger than that caused by the capillary-driven mechanism, i.e. the flow-driven fragmentation mech-anism is dominant for the currently investigated sample. After the solidification process, four frecklesformed at the casting corners on the shadowed side, whereas it was freckle-free on the bright side.

AB - Freckles, a significant issue encountered during the directional solidification of superal-loys, are recognised by a trail of equiaxed grains parallel to the direction of gravity accompanied bylocal eutectic enrichment. In the current study, a mixed-columnar-equiaxed multiphase volume-av-erage solidification model was employed to study the formation of freckles in superalloy casting.Fragments produced via flow-driven and capillary-driven fragmentation mechanisms are consideredas the source of spurious grains. The transport and the growth/remelting of the fragments are consid-ered. According to the simulation results, some segregation channels develop at the corners of thecasting. Flow-driven fragments are produced in/around the segregation channels, whereas capillary-driven fragments are produced at a certain depth of the mushy zone across the entire section of thecasting. The fragmentation rate caused by the flow-driven mechanism is several orders of magnitudelarger than that caused by the capillary-driven mechanism, i.e. the flow-driven fragmentation mech-anism is dominant for the currently investigated sample. After the solidification process, four frecklesformed at the casting corners on the shadowed side, whereas it was freckle-free on the bright side.

KW - formation of spurious grains

KW - formation of spurious grains and freck- les

KW - spurious grains and freck- les

KW - directional solidification

KW - superalloys

U2 - 10.1088/1757-899X/1281/1/012059

DO - 10.1088/1757-899X/1281/1/012059

M3 - Paper

T2 - MCWASP XVI IOP Conf. Series: Materials Science and Engineering

Y2 - 18 June 2023 through 23 June 2023

ER -