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DOE OSTI · 3374483

Additive manufacturing of mullite ceramic by digital light processing

Tsai, Jung-Ting [National Taiwan University of Science and Technology, Taipei City (Taiwan); Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000030360462X)·Thomas, Jonova [Argonne National Laboratory (ANL), Argonne, IL (United States)]·Chuang, Andrew Chihpin P. [Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)] (ORCID:000000030295381X)·Du, Wenchao [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000022953954X)·Singh, Dileep [Argonne National Laboratory (ANL), Argonne, IL (United States)]
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Abstract

Mullite material was successfully additively manufactured using digital light processing (DLP). The printed geometry involves a one-step process of pyrolysis, de-binding, and sintering under a plain atmosphere to achieve an average of 76 % ceramic yield and linear shrinkage of 12 %. Furthermore, the thermal profile was carefully controlled to obtain consistent phases in which the XRD shows a mullite phase. Here, in addition, the Weibull analysis was conducted on the sintered flexural specimens, showing a Weibull modulus (m) of 13.05 with a characteristic strength (σ 0 ) of 94.96 MPa. Synchrotron microtomography was performed on the sintered specimens, which showed two distinct porosity distributions (small and large). Large porosity (non-spherical elongated) is the primary cause of decreased material strength, while small porosity (spherical) is the sintering product. The measured thermal conductivity of the specimens was in the range of 2.7–3.1 W/m∙k and decreased with an increase in temperature. Lastly, large-scale prototypes were printed concurrently with a fine resolution of 25 μm without any compromise on the predetermined design and structure.

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Tsai, Jung-Ting [National Taiwan University of Science and Technology, Taipei City (Taiwan); Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000030360462X), Thomas, Jonova [Argonne National Laboratory (ANL), Argonne, IL (United States)], Chuang, Andrew Chihpin P. [Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)] (ORCID:000000030295381X), Du, Wenchao [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000022953954X), Singh, Dileep [Argonne National Laboratory (ANL), Argonne, IL (United States)]. 2025-02-26. Additive manufacturing of mullite ceramic by digital light processing. https://doi.org/10.1016/j.ceramint.2025.02.383

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