A Coupled Thermal-Mechanical-Oxidative Model for Predicting Oxidation and Stress Affected by Cracks

International Journal of Mechanical Sciences, Год журнала: 2025, Номер unknown, С. 110131 - 110131

Опубликована: Март 1, 2025

Язык: Английский

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Improved Thin-Kerf Processing in Cf/SiC Composite by Waterjet-Guided Nanosecond Laser Decreases Oxidation and Thermal Effect

Materials, Год журнала: 2025, Номер 18(7), С. 1560 - 1560

Опубликована: Март 29, 2025

As a hard and brittle material, the processing of Cf/SiC ceramic matrix composites (CMCs) faces significant challenges, especially in small-sized shapes. To address this challenge, laser with gas-assisted nanosecond (GNL) waterjet-guided (WNL) modes were applied to fabricate thin kerfs composite. The surface morphology, microstructure, chemical composition processed composite investigated comparatively. results revealed that coupling helium GNL mode could make full use energy, but resulted spattering kerf margin recast layer surface, accompanied by obvious oxidation, while waterjet WNL decreased oxidation significantly removed remelting debris, which produced clear flat surface. Due taper caused energy dissipation, single-path had limited depth. maximum depth prepared was about 328 μm, 302 μm. multi-path through composite, medium obviously influenced morphology microstructure underlying region. varied transited from top layer, covered oxide particles some cracks, bottom featured micro-grooves small oxides. consistently smooth clean broken carbon fiber residual SiC matrix. slow dissipation open environment bigger HAZ relatively serious local phase transformation degradation. isolation condition rapid cooling restrained almost keeping original microstructure. thicknesses GNL- WNL-processed 200 μm 100 respectively. lower thermal damage is instructive for

Язык: Английский

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Optimization of process parameters of ultrasonic‐assisted end face grinding of C_f/SiC composites

Journal of the American Ceramic Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 23, 2025

Abstract Carbon fiber–reinforced ceramic matrix (C f /SiC) composites are featured with high strength, high‐temperature resistant, and low density, become an important candidate thermal structural material for the hot end components of high‐performance aero‐engines. Due to their properties hardness, brittleness, inhomogeneity, anisotropy, ultrasonic‐assisted grinding is a commonly used method process C /SiC composites. The complex nonlinear mapping relationship between machining parameters quality needs be clarified. Taguchi L16 orthogonal array was carry out experiment in paper. Combined response surface method, prediction models roughness force were established, more than 95%. experimental results analyzed by signal‐to‐noise ratio analysis, variance method. effects spindle speed, feed rate, depth, ultrasonic amplitude on investigated. influence obtained. Finally, genetic‐particle swarm algorithm optimize under different weights, respectively, optimal

Язык: Английский

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Precision machining of alumina-reinforced ceramic matrix composites by femtosecond laser

The International Journal of Advanced Manufacturing Technology, Год журнала: 2025, Номер unknown

Опубликована: Май 3, 2025

Язык: Английский

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Combined hybrid machining of laser ablation-drilling small holes in Cf/SiC composites

Ceramics International, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 1, 2024

Язык: Английский

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Fabrication and mechanical properties of 2D C_f/SiC composites by joint process of vacuum bag molding, PIP, and RMI

Journal of the American Ceramic Society, Год журнала: 2024, Номер unknown

Опубликована: Дек. 23, 2024

Abstract The structural integrity of continuous carbon fiber‐reinforced silicon carbide (C f /SiC) composites is often compromised by fiber damage during high‐temperature sintering, nonuniform distribution, and the brittleness ceramic matrix, which limits their broader application. This study reported an innovative approach vacuum bagging combined with thermal press curing, followed precursor infiltration pyrolysis (PIP) reaction melt (RMI), densification to fabricate a C /SiC composite remarkable properties. pyrolytic (PyC)/boron nitride (BN) double interface layers were deposited via chemical vapor deposition (CVD). Results revealed that curing effectively eliminated bond‐line defects, while PyC/BN layer further improved toughening . combination showed optimal strength 330 ± 30 MPa 7.4 0.5 m 1/2 , representing increases 50% 47%, respectively. failure mechanisms responsible for mechanical behavior are gained through macro microanalysis. work provides high‐performance, economical, convenient process enhancing performance composites, providing valuable insights development matrix composites.

Язык: Английский

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Oxidation behavior of supersonic air plasma sprayed Yb2SiO5/Si and Yb2Si2O7/Si coating for CVD-SiC coated C/C composites in wet oxygen at 1773 K: Experimental and first-principle calculation

Ceramics International, Год журнала: 2024, Номер unknown

Опубликована: Дек. 1, 2024

Язык: Английский

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