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To address the issues of burr formation, structural deformation, and tearing in the conventional machining of Nomex honeycomb composites, this study aims to clarify the mechanisms by which ultrasonic vibration-assisted cutting enhances machining quality. A multi-scale analysis framework is developed to examine the effects of ultrasonic vibration on fiber distribution, cell-level shear response, and the overall cutting mechanics. At the microscale, analyses show that ultrasonic vibration mitigates stress concentrations, thereby shortening fiber length. At the mesoscale, elastic buckling and plastic yielding models show that ultrasonic vibration lowers shear strength and modifies the deformation. A macro-scale comparison of cutting behavior with and without ultrasonic vibration was conducted. The results indicate that the intermittent contact effect induced by vibration significantly reduces cutting force. Specifically, at an amplitude of 40 μm, the cutting force decreased by approximately 29.7% compared to the condition without ultrasonic vibration, with an average prediction error below 8.6%. Compared to conventional machining, which causes the honeycomb angle to deform to approximately 130°, ultrasonic vibration preserves the original 120° geometry and reduces burr length by 36%. These results demonstrate that ultrasonic vibration effectively reduces damage through multi-scale interactions, offering theoretical guidance for high-precision machining of fiber-reinforced composites.
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http://dx.doi.org/10.3390/ma18153476 | DOI Listing |
Ultrasonics
September 2025
Faculty of Land Resource Engineering, Kunming University of Science and Technology, Yunnan 650093, China; Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area, Ministry of Natural Resources of the People's Republic of China, Yunnan Province, Kunming, Yunnan
Identifying and predicting the catastrophic failure of brittle rock remains a challenging task, yet it is crucial for developing early warning systems and preventing dynamic rock hazards. In this study, we employed the propagative parameters of ultrasonic waves and information from acoustic emission (AE) events to characterize the brittle failure of a flawed sandstone sample under uniaxial compression. A sliding event window method was developed to obtain the temporal b-value, effectively revealing microcrack growth based on the frequency-magnitude distribution of AE events.
View Article and Find Full Text PDFNanoscale Adv
August 2025
Department of Chemistry and Industrial Chemistry & INSTM RU, University of Genoa Via Dodecaneso 31 16146 Genova (GE) Italy
Bismuth ferrite (BiFeO), a perovskite oxide with both ferroelectric and antiferromagnetic properties, has emerged as a promising material for environmental cleanup due to its piezo-photocatalytic activity. The material's ability to degrade organic pollutants, such as azo dyes, under both light irradiation and mechanical stress (ultrasonic waves) offers a dual-action mechanism for efficient wastewater treatment. In this work, we explore the synthesis of BiFeO nanoparticles a simple sol-gel method, followed by characterization of their structural, magnetic, and photocatalytic properties.
View Article and Find Full Text PDFACS Omega
September 2025
Petroleum Exploration and Engineering Lab (LENEP), North Fluminense State University (UENF), Macaé 27930-480, Brazil.
Understanding seismic attenuation in carbonate rocks is critical for improving reservoir characterization and fluid monitoring during hydrocarbon exploration. This study investigated the behavior of P-wave attenuation (1/ ) during fluid substitution from saltwater to oil in coquina samples from the Morro do Chaves Formation, an analogue of Brazilian pre-salt reservoirs. Laboratory experiments were conducted at an ultrasonic frequency (1.
View Article and Find Full Text PDFAnal Chim Acta
November 2025
Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), Universidade Estadual de Campinas (UNICAMP), Rua Pedro Zaccaria 1300, Limeira, 13484-350, São Paulo, Brazil. Electronic address:
Background: Monitoring industrial processes is critical for ensuring consistent product quality, as consumers expect uniformity across different production batches. In the case of herbal extracts, such as rosemary hydroalcoholic extracts, it is essential to control the yield of target compounds to maintain both the expected quality and safety. Typically, these extracts are produced in an extractor and then analyzed separately in a laboratory (offline).
View Article and Find Full Text PDFCarbohydr Polym
November 2025
Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, NE1 8ST Newcastle Upon Tyne, United Kingdom; Centre for Biomaterials and Tissue Engineering (CBIT), Universitat Politècnica de València, 46022, Valencia, Spain. Electronic address: joel.l.g.hernandez@north
Polysaccharides, widely used in food, pharmaceutical and industrial sectors, are abundant in Theobroma species pod husk waste (T. cacao, T. grandiflorum and T.
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