{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T17:25:44Z","timestamp":1792689944614,"version":"4.5.0"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T00:00:00Z","timestamp":1674086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Skin is the largest organ of many animals. Its protective function against hostile environments and predatorial attack makes high mechanical strength a vital characteristic. Here, we measured the mechanical properties of bass fish skins and found that fish skins are highly ductile with a rupture strain of up to 30\u201340% and a rupture strength of 10\u201315 MPa. The fish skins exhibit a strain-stiffening behavior. Stretching can effectively eliminate the stress concentrations near the pre-existing holes and edge notches, suggesting that the skins are highly damage tolerant. Our measurement determined a flaw-insensitivity length that exceeds those of most engineering materials. The strain-stiffening and damage tolerance of fish skins are explained by an agent-based model of a collagen network in which the load-bearing collagen microfibers assembled from nanofibrils undergo straightening and reorientation upon stretching. Our study inspires the development of artificial skins that are thin, flexible, but highly fracture-resistant and widely applicable in soft robots.<\/jats:p>","DOI":"10.3390\/ma16030953","type":"journal-article","created":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T06:22:10Z","timestamp":1674109330000},"page":"953","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Superior Damage Tolerance of Fish Skins"],"prefix":"10.3390","volume":"16","author":[{"given":"Emily","family":"Zhang","sequence":"first","affiliation":[{"name":"State College Area High School, State College, PA 16801, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chi-Huan","family":"Tung","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luyi","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Engineering Science and Mechanics, The Pennsylvania State University, State College, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu Ren","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,19]]},"reference":[{"key":"ref_1","unstructured":"Jablonski, N.G. 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