{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T04:19:21Z","timestamp":1791260361127,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T00:00:00Z","timestamp":1778284800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52175373"],"award-info":[{"award-number":["52175373"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52175373"],"award-info":[{"award-number":["52175373"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2024YFB3411102"],"award-info":[{"award-number":["2024YFB3411102"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005270","name":"Fujian Provincial Department of Science and Technology","doi-asserted-by":"publisher","award":["2024J01240"],"award-info":[{"award-number":["2024J01240"]}],"id":[{"id":"10.13039\/501100005270","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2024J01240"],"award-info":[{"award-number":["2024J01240"]}],"id":[{"id":"https:\/\/ror.org\/00rgzpv08","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002822","name":"Central South University","doi-asserted-by":"publisher","award":["Kfkt2024-06"],"award-info":[{"award-number":["Kfkt2024-06"]}],"id":[{"id":"10.13039\/501100002822","id-type":"DOI","asserted-by":"publisher"}]},{"award":["Kfkt2024-06"],"award-info":[{"award-number":["Kfkt2024-06"]}],"id":[{"id":"https:\/\/ror.org\/00f1zfq44","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Composite components with variable-thickness structures often suffer from insufficient forming pressure during curing due to complex pressure transfer in regions with abrupt thickness changes, which easily causes void defects and degrades component performance. In this study, a mechanical vibration-assisted double vacuum bag process is proposed. Finite element analysis of the vibration energy field in saturated porous composites is conducted, and curing experiments for variable-thickness specimens are designed. The effects of vibration, vacuum, and their synergy on void characteristics and mechanical properties are studied using microscopic characterization and mechanical tests. The results indicate that vibration can effectively facilitate gas discharge and accelerate resin flow, while the double vacuum bag process reduces gas discharge resistance in the early curing stage by delaying the vacuum negative pressure application, yet it also results in insufficient resin flow due to this delay. Through the synergistic optimization of vibration-assisted energy field parameters and the double vacuum bag process, gas-induced and flow-induced voids can be effectively suppressed while ensuring curing efficiency, reducing the macroscopic porosity of variable-thickness regions from 8.34% (single vacuum bag process) to 0.43%. This study provides a new approach for the high-quality curing and manufacturing of variable-thickness composite components.<\/jats:p>","DOI":"10.3390\/polym18101170","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T10:50:52Z","timestamp":1778496652000},"page":"1170","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Void Suppression Method of CFRP Variable-Thickness Structure Components by Vibration-Assisted Curing Process"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-7944-4300","authenticated-orcid":false,"given":"Shunming","family":"Yao","sequence":"first","affiliation":[{"name":"College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9419-4149","authenticated-orcid":false,"given":"Lihua","family":"Zhan","sequence":"additional","affiliation":[{"name":"Light Alloys Research Institute, Central South University, Changsha 410083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chenglong","family":"Guan","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dechao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Light Alloys Research Institute, Central South University, Changsha 410083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miaomiao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Light Alloys Research Institute, Central South University, Changsha 410083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,9]]},"reference":[{"key":"ref_1","first-page":"14","article-title":"Research and application progress of key technologies for composites cryogenic tanks","volume":"64","author":"Wu","year":"2021","journal-title":"Aeronaut. 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