{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:53:38Z","timestamp":1787028818359,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T00:00:00Z","timestamp":1643673600000},"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>Bird strike, volcanic rock, hailstones, micrometeoroids, or space debris can cause damage to aircraft and space vehicles, therefore their composite materials must have high impact resistance to maximize safety. In a 55% wt. CaCO3 compression molded short glass fiber polyester GFRP-BMC (bulk molded compound), shortening the nominal 6.4 mm fiber length formulation, by 30 min extended mixing, to 0.44 mm was found to increase Charpy impact values, auc, without a change in the compression molding equipment. Specimens were cut from square panels in a spiral configuration in conformity with ASTM D 6110-02 for orthotropic panels, the flow direction approximately radially outward from the charge. At a median-fracture probability of Pf = 0.50, extended mixing improved auc by 29%, from 7.43 to 9.59 kJm\u22122, and for each solidification texture angle, namely, 0 to 90 (random), 71, 45 and 18 deg, the auc increased by 25% (6.26 to 7.86 kJm\u22122), 18% (9.36 to 11.07 kJm\u22122), 35% (7.68 to 10.37 kJm\u22122), and 20% (6.96 to 8.36 kJm\u22122), respectively. This strengthening can be explained by an increased number of thermal compressive stress sites between the glass fiber and matrix due to a difference in the coefficient of thermal expansion (CTE) during cool-down, and shrinkage, with an increased number of spaces between fibers, |Sf| from 217 to approximately 2950 per mm3, enhancing impact energy.<\/jats:p>","DOI":"10.3390\/ma15031145","type":"journal-article","created":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T22:16:18Z","timestamp":1643753778000},"page":"1145","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Increasing Impact Strength of a Short Glass Fiber Compression Molded BMC by Shortening Fibers without Change in Equipment"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2016-0899","authenticated-orcid":false,"given":"Michael C.","family":"Faudree","sequence":"first","affiliation":[{"name":"Faculty of Liberal Arts and Science, Tokyo City University, Yokohama-shi 224-8551, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshitake","family":"Nishi","sequence":"additional","affiliation":[{"name":"Graduate School of Engineering, Tokai University, Hiratsuka-shi 259-1292, Japan"},{"name":"Kanagawa Institute of Industrial Science and Technology (KISTEC), Ebina-shi 243-0435, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michelle","family":"Salvia","sequence":"additional","affiliation":[{"name":"Ecole Centrale de Lyon, Ecully, CEDEX, 69134 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1170","DOI":"10.1177\/002199838802201207","article-title":"Characterization of Damage and Fracture Processes in Short Fiber BMC Composites by Acoustic Emission","volume":"22","author":"Faudree","year":"1988","journal-title":"J. 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