{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T14:51:59Z","timestamp":1793458319053,"version":"4.5.0"},"reference-count":20,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"content-version":"vor","delay-in-days":76,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Manipal Academy of Higher Education, Manipal"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>This study investigates the flexural behaviour and microstructure\u2013property relationships of natural silk fabric\u2013reinforced epoxy composites fabricated using a cast moulding route. Three rectangular specimens (100\u2009\u00d7\u200920\u2009\u00d7\u20095\u00a0mm) were tested under three-point bending in accordance with ASTM D790 with a 60\u00a0mm support span. The composites were produced at moderate fibre volume fractions (approximately 20\u201340 vol%), and their density and void content were evaluated using mass\u2013volume measurements and optical image analysis. The measured flexural strength ranged between 100 and 130\u00a0MPa, with results reported as mean values along with standard deviation. The composites exhibited a pseudo-ductile response characterized by an initial linear elastic region followed by progressive damage and gradual post-peak softening. Although peak stresses were comparable, clear differences in strain-to-failure and post-peak stability were observed, indicating that deformation behaviour is governed primarily by interfacial integrity and microstructural heterogeneity. Multiscale characterization using optical microscopy and scanning electron microscopy (SEM) was carried out to establish structure\u2013property relationships. Optical observations revealed that voids and non-uniform resin impregnation influence crack initiation and propagation. SEM-based fractography identified dominant failure mechanisms including matrix cracking, interfacial debonding, fibre pull-out, and localized fibre fracture. Specimens with improved impregnation showed better interfacial continuity and crack-bridging, whereas defect-rich regions exhibited premature damage initiation and unstable crack growth. The results demonstrate that load transfer and flexural stability are governed by interfacial stress transfer and processing-induced heterogeneity. The study provides a mechanistic interpretation of flexural behaviour and offers a basis for positioning silk\u2013epoxy composites within natural fiber reinforced systems.<\/jats:p>","DOI":"10.1038\/s41598-026-55528-3","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T14:24:21Z","timestamp":1780410261000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Flexural performance and microstructural correlation of natural silk fabric-reinforced epoxy composites"],"prefix":"10.1038","volume":"16","author":[{"given":"Sampath Suranjan","family":"Salins","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sawan","family":"Shetty","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deepak","family":"Doreswamy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thamme","family":"Gowda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H. 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M, A., Silk as a Natural Reinforcement: Processing and Properties of Silk\/Epoxy Composite Laminates, Materials (Basel), 11(11), 2135 (2018). https:\/\/doi.org\/10.3390\/ma11112135","DOI":"10.3390\/ma11112135"},{"key":"55528_CR5","doi-asserted-by":"publisher","first-page":"11939","DOI":"10.1038\/s41598-017-11919-1","volume":"7","author":"Y Kang","year":"2017","unstructured":"Kang, Y., Sujun, W., Juan, G., Zhengzhong, S., Robert, O. & R Enhancing the Mechanical Toughness of Epoxy-Resin Composites Using Natural Silk Reinforcements. Sci. Rep. 7, 11939. https:\/\/doi.org\/10.1038\/s41598-017-11919-1 (2017).","journal-title":"Sci. Rep."},{"issue":"1","key":"55528_CR6","doi-asserted-by":"publisher","first-page":"16","DOI":"10.37934\/arms.69.1.1628","volume":"69","author":"Z Zuraidah","year":"2020","unstructured":"Zuraidah, Z., Noor, I., M, S., Mat, Y. & U, W Characteristics of Continuous Unidirectional Silk Fibre Reinforced Epoxy Composites. J. Adv. Res. Mater. 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All experimental procedures followed institutional and national guidelines for research integrity and ethics.","order":2,"name":"Ethics","label":"Ethical Approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"\u2018Consent to Participate declaration: not applicable\u2019.","order":3,"name":"Ethics","label":"Consent to Participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Consent to Publish declaration: not applicable\u2019.","order":4,"name":"Ethics","label":"Consent to Publish","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"No supplementary information is available for this paper.","order":5,"name":"Ethics","label":"Supplementary Information","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"25550"}}