MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
He Li,Yongsheng Liu,Wenbo Li,Yansong Liu,Qingfeng Zeng
In order to aid dissolution of ceramic cores, calcium oxide was added to alumina to fabricate composite ceramics cores via 3D printing . The effect of sintering temperature and addition of calcia (5 wt%) on the microstructure and properties of the sintered ceramics were investigated. CaAl 12 O 19 formed via a chemical reaction between alumina and calcium oxide at high temperature, and CaAl 12 O 19 could be clearly seen in scanning electron microscope (SEM) images, energy dispersive X-ray spectroscopy (EDS) measurements, and X-ray diffraction (XRD) measurements. The sintered composite ceramics had porous structure and uniform elemental distribution. The sintered ceramics exhibit greater shrinkage, bulk density, and flexural strength when the sintering temperature is higher. The CaAl 12 O 19 grains provide connections between alumina grains, which ensures the sintered ceramics have greater strength and less deformation compared to un-sintered ceramics.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Virtual and Physical Prototyping
·
2025
·
IF 8.8
Yongkang Yang,Xiqing Xu,Boran Wang,Shiyuan Li,Ziqi Jia,Xusen Guo,Shuhuai Wang,Shuxin Niu,Xin Li
Vat photopolymerization (VPP) 3D printing technology is suited for intricate ceramic core forming due to its design freedom. However, solving the lateral over-cure width while formation is crucial. Graphene was used in VPP-3D printing of silica-based ceramic cores to examine its effects on forming and sintering, and a desirable curing coefficient was presented to evaluate the forming accuracy of single layer. A straightforward model using a modified Beer–Lambert law based on exposure time rather than exposure power predicts the effect of graphene on the VPP process at consistent curing depth and exposure time and clarifies how the curing process affects flexural strength and surface quality. The optimal graphene content was determined by double bond conversion rate, structural anisotropy, and mechanical properties. Increasing graphene concentration reduces curing sensitivity and exposure time threshold, allowing more liquid phase to cure and improving double bond conversion and interlayer bonding. However, excess graphene increases the conversion rate and stress concentration of green body. According to microstructural studies, extra graphene enhanced the likelihood of crack reformation after sintering. The ceramic cores had optimal forming and sintering capabilities with 0.6 wt.‰ graphene content. The approach offers significant insights for enhancing VPP ceramic 3D printing.
研究领域:
材料科学
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增材制造
✓ 已验证
产品关联
DOI
高影响因子
China Foundry
·
2025
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IF 2.3
Yang Yong-kang,Wang Bo-ran,Jia Zi-qi,Niu Shu-xin,Li Xin,Guo Ya-jie,Xu Xi-qing
Vat photopolymerization (VPP) 3D printing is an optimized technology for complex-shaped ceramic cores, in which the solid loading of ceramic slurries greatly influences the microstructure and property of the final ceramic parts. However, the high solid loading of slurries is highly limited by the high viscosity. In this study, silica-based ceramic core slurries with solid loading up to 68vol.% were achieved by the composition design to optimize the performance, considering the curing, rheological, and double bond conversion rate. The slurries demonstrate superior curing and rheological performance with mass ratio of monomers being 3:2 and mass fraction of BYK111 being 4wt.%. Afterwards, the impact of solid loading on the morphology and mechanical properties was investigated. As the solid loading increases, the microstructure becomes gradually dense, leading to an improved flexural strength of 19.5 MPa. Additionally, the sintering shrinkage becomes more uniform, satisfying the casting requirements effectively. This work serves as a guide for the preparation of ceramic slurries with a high solid loading.
研究领域:
材料科学
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3D 打印技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
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IF 5.2
Xiaofei Zhai,Jingyi Chen,Yaru Wang,Ruyue Su,Xiong Gao,Xueqin Zhang,Hua Jin,Rujie He
When preparing ceramic materials, high porosity and high strength are often played against each other. How to balance porosity and strength has become a core issue in the 3D printing of ceramic cores. In this work, alumina ceramic cores with a high porosity (36.93%) and a high flexural strength (75.4 MPa) were prepared by combining the vat photopolymerization 3D printing with sacrificial templating. The porosity of alumina ceramic cores was improved by the sacrificial templating method, and the flexural strength was enhanced with alumina particle grading. The effects of pore former (PMMA) content and particle size on the shrinkage, porosity, microstructure, and comprehensive performance of alumina ceramic cores were investigated to reveal the mechanism of simultaneous high porosity and high strength.
研究领域:
材料科学
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制造工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 8
·5400-5411
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IF 3.5
Xiaofei Zhai,Jingyi Chen,Ruyue Su,Xiong Gao,Xueqin Zhang,Rujie He
The complex ceramic core used for hollow turbine blades requires high porosity and flexural strength. This work combined vat photopolymerization 3D printing with sacrificial template method to prepare Al 2 O 3 ceramic cores with strip-shaped pores using polyamide 6 (PA6) fibers as templates. When the porosity was greater than 30%, the maximum flexural strength reached up to 110.48 MPa. The sacrificial templating method improved the porosity of Al 2 O 3 ceramic cores, forming an internal porous structure that combined strip-shaped large pores with irregularly shaped small pores. The influences of PA6 fiber content and diameter on the shrinkage, porosity, microstructure, and comprehensive properties of alumina ceramic cores were studied, revealing the mechanism of the coexistence of high porosity and high strength.
研究领域:
材料科学
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制造工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2022
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IF 5.532
Weizhe Tang,Tong Zhao,Rui Dou,Li Wang
We prepare bimodal particle size photo-curable ceramic pastes with high solid loadings (up to 65 vol %) and fabricate porous alumina ceramic cores with complex shapes via ceramic stereolithography (Cer-SLA) 3D printing technique. The sintering temperature is carefully selected, ranging from 1500 °C to 1650 °C, and a high holding time (>4 h) is applied to guarantee that the materials can withstand the subsequent high temperature (>1500 °C) casting process for single-crystal nickel-based superalloy hollow turbine blades. Herein, the originally spherical fine particles are found to become platelet-like after sintering, and the forming mechanism is discussed in detail. In addition, we explore the influence of platelet-like particles, coarse particles and sintering process on the microstructural evolution of alumina particles, and reveal the relationship between microstructure and properties of ceramic cores. These results illustrate that the proposed materials for SLA 3D printing exhibit a great potential in the fabrication of complex-shaped alumina ceramic cores for high-precision investment casting, e.g., manufacturing single-crystal nickel-based superalloy hollow turbine blades for an advanced aircraft engine.
研究领域:
材料科学
·
制造工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）