CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Ruiguang Chen,Qin Lian,Dichen Li,Xiaoning He,Shuaiwei Wang,Jian Zhuang
Diamond/SiC composites with high thermal conductivity are important materials for electronic industry, especially electronic packaging, but their complex structures and high-precision manufacturing are still challenging issues. Stereolithography-based manufacturing method combined with the reactive melt infiltration to make diamond/SiC composites with high-precision complex structures has been proposed in this paper. Diamond particles were used as the raw material, and as the particle size is a key factor affecting composite performance its influence was studied by means of measuring parameters, examining microstructure, and detecting components, whereas related mechanisms are discussed as necessary. Subsequently, a diamond/SiC composite with the thermal conductivity of 245.68 W/(m K) has been prepared and used in experiment. The experiment shows that the precision is affected by light-scattering and bending in the printing plane and in the vertical plane respectively, with the size errors of 0.25 and 0.12 mm.
研究领域:
材料科学
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增材制造
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY
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2025
·
IF 3.7
Tianyu Bai,Chenglin Yan,Xiaoyuan Li,Lianxin Zhang,Minheng Ye,Chao Wang
Magnetorheological finishing (MRF) is being widely utilized in Semiconductor and optical processing. The properties of the finishing fluid have a great influence on the finishing quality. This study revealed that sodium polystyrene sulfonate (PSS), when employed as a dispersant in the finishing fluid, effectively enhances the polishing performance and maintains the processing stability of the finishing fluid. In the MRF processing, the group with the addition of 0.2 % PSS achieved a reduction in the roughness (Rq) of the fused silica (FS) workpiece to 1.02 nm compared to 4.3 nm in the control group. The PSS elevated the surface potential of abrasive particles , impeding abrasive agglomeration by reinforcing electrostatic repulsion . Simultaneously, the operation life of the finishing fluid significantly extends more than 3 times. The addition of PSS resulted in a significant decrease in the oxidation of Carbonyl iron particles (CIPs). Energy spectrum analysis revealed that diamond abrasives scratched the CIPs. Scratched CIPs were prone to be oxidized to Fe 3+ , thus leading to the significant failure of the finishing fluid. PSS adsorb to particle surfaces, creating steric hindrance that reduces friction between abrasives and CIPs. The MRF fluid with PSS exhibited a notable reduction of Fe 3+ concentration. Both mechanisms concurrently enhanced the processing stability.
研究领域:
材料科学
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表面工程
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精密制造
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胶体化学
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光学加工
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半导体工艺
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhe Wang,Zhenkai Mu,Xuye Wang,Wei Wang,Xuerui Dai,Shibo Ma,Xinni Zhang
Vat photopolymerization technology has garnered significant attention in the field of ceramic additive manufacturing due to its high precision and efficient forming capabilities. However, a fundamental challenge remains in balancing the curing depth and printing accuracy during the fabrication of Si 3 N 4 ceramics. To address this issue, this study proposes a novel strategy for the synergistic modulation of slurry optical properties via the integration of a photoinitiator (PI, Irgacure 819), a UV absorber (UA, UV-531), and an oxygen scavenger (OI, BHT). Through a full-factorial experimental design, a multivariate nonlinear model was established. The results demonstrate that the photoinitiator (PI) enhances the polymerization efficiency by generating reactive radicals under UV exposure, while the UV absorber (UA) suppresses lateral over-curing by increasing the ultraviolet absorption coefficient, and the oxygen scavenger (OI) mitigates oxygen-induced inhibition of polymerization. The synergistic effects of these three additives maintain the curing depth within the range of 67.3–86.7 μm, while significantly improving the printing accuracy of submillimeter-scale microholes. The relative errors for square holes ranging from 200 to 500 μm were reduced to less than 2 %. The optimized slurry formulation ensures sufficient curing depth while markedly enhancing printing precision, enabling the rapid fabrication of high-resolution complex structures. This work provides a solid foundation for the advancement of vat photopolymerization of silicon nitride ceramics.
研究领域:
材料科学
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陶瓷增材制造
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光聚合化学
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精密制造
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功能陶瓷
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2024
·Vol. 64
·期 5
·2082-2095
·
IF 3.2
Yilei Wang,Can Weng,Zihao Fei,Huijie Sun,Bingyan Jiang
The demolding process in micro-injection molding constitutes a critical phase, exerting a decisive influence on the quality of polymer microstructures. In this study, the demolding forces of PMMA microfluidic chips were measured under different demolding temperatures, packing pressures, and demolding speeds by using pure nickel (Ni) mold insert. The dimensional deviations of the microchannels with different aspect ratios were analyzed. In addition, the effect of mold insert modification on the demolding force was further analyzed. The results showed that the effect of demolding temperature on the demolding force was the most significant, and the peak demolding force decreased with the decrease in temperature. The width of the microchannels increased and the depth decreased after demolding, while the opposite results were observed for the micro-mixing structures. However, the dimensional deviation of the micro-mixing structures was larger than that of the microchannels. Using the optimal molding parameters, the peak demolding force could be reduced from 114.0 N at 110°C to 47.0 N, a decrease of 58.8%. It is noteworthy that, when the microchannel was narrower than 100 μm, achieving precise replication of microchannel dimensions became progressively more challenging as the microchannel width decreased. Using the Ni-WS 2 mold insert with low surface energy and low friction coefficient, the demolding force could be further reduced by 38.3%. The effect of the molding quality of microfluidic chip microstructures on the mixing performance of heavy metals was demonstrated by micro-mixing experiments. Highlights Demolding temperature crucially affects microstructure dimensions. Optimal parameters and modified mold insert reduce demolding force by 38.3%. Dimensional deviation increases with the increase of microchannel aspect ratio. Optimized microfluidic chip enhances Co 2+ chemiluminescence by 6.42%.
研究领域:
微流控技术
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聚合物加工
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精密制造
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材料科学
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表面工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）