{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T10:31:39Z","timestamp":1780050699136,"version":"3.53.1"},"reference-count":57,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,26]],"date-time":"2024-04-26T00:00:00Z","timestamp":1714089600000},"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>It is vital to maximize the safety of outdoor constructions, airplanes, and space vehicles by protecting against the impact of airborne debris from increasing winds due to climate change, or from bird strikes or micrometeoroids. In a widely-used compression-molded short glass fiber polyester bulk-molded compound (SGFRP-BMC) with 55% wt. CaCO3 filler, the center of the mother panel has lower impact strength than the outer sections with solidification texture angles and short glass fiber (SGF) orientations being random from 0 to 90 degrees. Therefore, a new double-step process of: (1) reducing commercial fiber length without change in molding equipment; followed by a (2) 0.86 MGy dose of homogeneous low-voltage electron beam irradiation (HLEBI) to both sides of the finished samples requiring no chemicals or additives, which is shown to increase the Charpy impact value (auc) about 50% from 6.26 to 9.59 kJm\u22122 at median-accumulative probability of fracture, Pf = 0.500. Shortening the SGFs results in higher fiber spacing density, Sf, as the thermal compressive stress site proliferation by action of the CTE difference between the matrix and SGF while the composite cools and shrinks. To boost impact strength further, HLEBI provides additional nano-compressive stresses by generating dangling bonds (DBs) creating repulsive forces while increasing SGF\/matrix adhesion. Increased internal cracking apparently occurs, raising the auc.<\/jats:p>","DOI":"10.3390\/ma17092036","type":"journal-article","created":{"date-parts":[[2024,4,26]],"date-time":"2024-04-26T09:26:02Z","timestamp":1714123562000},"page":"2036","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A New Double-Step Process of Shortening Fibers without Change in Molding Equipment Followed by Electron Beam to Strengthen Short Glass Fiber Reinforced Polyester BMC"],"prefix":"10.3390","volume":"17","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"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1280","DOI":"10.2320\/matertrans.M2018068","article-title":"A new glass fibered reinforced composite with improved Charpy impact properties at low and high temperatures beyond the extremes of aircraft flight","volume":"59","author":"Faudree","year":"2018","journal-title":"Mater. Trans."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"805","DOI":"10.1515\/polyeng-2014-0330","article-title":"Morphology and thermomechanical properties of epoxy composites highly filled with waste bulk molding compounds (BMC)","volume":"35","author":"Matykiewicz","year":"2015","journal-title":"J. Polym. Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1177\/0892705705049560","article-title":"Strength and microscopic investigation of unsaturated polyester BMC reinforced with SMC-Recyclate","volume":"18","author":"DeRosa","year":"2005","journal-title":"J. Thermoplast. Compos. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1080\/00222348.2020.1844409","article-title":"Experimental Analysis and Optimization of Mechanical and Physical Properties of Light-Weight Bulk Molding Compound by Design of Experiment","volume":"60","author":"Rajaee","year":"2021","journal-title":"J. Macromol. Sci. Part B"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1080\/09243046.2016.1187821","article-title":"Development of a lightweight BMC material using fly ash","volume":"26","author":"Lee","year":"2017","journal-title":"Adv. Compos. Mater."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1877","DOI":"10.2320\/matertrans.M2013143","article-title":"Characterization of velocity profile of highly-filled GFRP-BMC through rectangular-duct shaped specimen during injection molding from SEM fiber orientation mapping","volume":"54","author":"Faudree","year":"2013","journal-title":"Mater. Trans."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2304","DOI":"10.2320\/matertrans.M2010121","article-title":"Tensile Strength Enhancement by Shortening Glass Fibers with Sub-Millimeter Length in Bulk Molding Polymer Compound","volume":"51","author":"Faudree","year":"2010","journal-title":"Mater. Trans."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1292","DOI":"10.2320\/matertrans.M2014070","article-title":"A Novel \u2018Fiber Spacing\u2019 Model of Tensile Modulus Enhancement by Shortening Fibers to Sub-Millimeter in an Injection-Molded Glass Fiber Reinforced Polymer Bulk Molding Compound (GFRP-BMC)","volume":"55","author":"Faudree","year":"2014","journal-title":"Mater. Trans."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5345","DOI":"10.1016\/j.matpr.2019.07.560","article-title":"Effect of fillers of various sizes on mechanical characterization of natural fiber polymer hybrid composites: A review","volume":"18","author":"Singh","year":"2019","journal-title":"Mater. Today Proc."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"106803","DOI":"10.1016\/j.compositesb.2019.05.014","article-title":"Effect of styrene-butadiene rubber and fumed silica nano-filler on the microstructure and mechanical properties of glass fiber reinforced unsaturated polyester resin","volume":"173","author":"Rajaee","year":"2019","journal-title":"Compos. Part B Eng."},{"key":"ref_11","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. Compos. Mater."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/0142-9418(94)90031-0","article-title":"Correlation Between Dynamic Mechanical Properties and State of Cure for Bulk Moulding Compounds","volume":"13","author":"Tadlaoui","year":"1994","journal-title":"Polym. Test."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.procir.2017.03.280","article-title":"Adirect process to reuse dry fiber production waste for recycled carbon fiber bulk molding compounds","volume":"66","author":"Saburow","year":"2017","journal-title":"Procedia CIRP"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"960","DOI":"10.1016\/j.compstruct.2017.09.100","article-title":"Comparison of filler-dependent mechanical properties of jute fiber reinforced sheet and bulk molding compound","volume":"203","author":"Mayer","year":"2018","journal-title":"Compos. Struct."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1226","DOI":"10.1016\/j.matpr.2017.11.205","article-title":"Physical Properties of Novel Kenaf Short Fiber Reinforced Bulk Molding Compounds (BMC) For Compression Moulding","volume":"5","author":"Sreenivasan","year":"2018","journal-title":"Mater. Today Proc."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1903","DOI":"10.1016\/j.compscitech.2007.12.018","article-title":"Analysis of the tensile behaviour of viscoelastically prestressed polymeric matrix composites","volume":"68","author":"Pang","year":"2008","journal-title":"Compos. Sci. Technol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1016\/S0263-8223(98)00032-4","article-title":"On the influence of pre-stress on the mechanical properties of a unidirectional GRE composite","volume":"40","author":"Hadi","year":"1997","journal-title":"Compos. Struct."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1177\/073168449901800308","article-title":"Fibre prestressed composites: Improvement of flexural properties through fibre prestressing","volume":"18","author":"Motahari","year":"1999","journal-title":"J. Reinf. Plast. Compos."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"117867","DOI":"10.1016\/j.compstruct.2023.117867","article-title":"Mould free laminated composites using eccentric fibre prestressing","volume":"331","author":"Jenkins","year":"2024","journal-title":"Compos. Struct."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4377","DOI":"10.1007\/BF00559325","article-title":"The mechanical behaviour of PVC short-fibre composites","volume":"20","author":"Yuan","year":"1985","journal-title":"J. Mater. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1016\/0266-3538(96)00039-5","article-title":"Effect of Interfacial Decohesion on Stiffness Reduction in a Random Discontinuous-Fibre Composite Containing Matrix Microcracks","volume":"56","author":"Meraghni","year":"1996","journal-title":"Compos. Sci. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1797","DOI":"10.1016\/S0008-6223(99)00048-2","article-title":"Surface properties of electrochemically oxidized carbon fibers","volume":"37","author":"Pittman","year":"1999","journal-title":"Carbon"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1016\/j.compositesa.2008.04.004","article-title":"The enhancement of carbon fiber modified with electropolymer coating to the mechanical properties of epoxy resin composites","volume":"39","author":"Hung","year":"2008","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"964","DOI":"10.1007\/s10853-010-4847-z","article-title":"Influence of cold remote nitrogen oxygen plasma treatment on carbon fabric and its composites with specialty polymers","volume":"46","author":"Tiwari","year":"2011","journal-title":"J. Mater. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Faudree, M.C., Uchida, H.T., Kimura, H., Kaneko, S., Salvia, M., and Nishi, Y. (2022). Advances in Titanium\/Polymer Hybrid Joints by Carbon Fiber Plug Insert: Current Status and Review. Materials, 15.","DOI":"10.3390\/ma15093220"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1016\/1359-835X(95)00065-A","article-title":"Influence on fibre length and concentration on the properties of glass fibre reinforced polypropylene: Tensile and flexural modulus","volume":"27","author":"Thomason","year":"1996","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1732","DOI":"10.1016\/j.compositesa.2008.08.001","article-title":"The influence of fibre length, diameter and concentration on the modulus of glass fibre reinforced polyamide 6,6","volume":"39","author":"Thomason","year":"2008","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/S1359-835X(96)00127-3","article-title":"Influence on fibre length and concentration on the properties of glass-fibre-reinforced polypropylene: Impact properties","volume":"28","author":"Thomason","year":"1997","journal-title":"J. Compos. Part A"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1179","DOI":"10.1016\/S0266-3538(96)00072-3","article-title":"Effects of fiber length and fiber orientation distributions on the tensile strength of short fiber reinforced polymers","volume":"56","author":"Fu","year":"1996","journal-title":"Compos. Sci. Technol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2743","DOI":"10.1016\/j.compscitech.2006.03.013","article-title":"Numerical simulation of matrix micro-cracking in short fiber reinforced polymer composites: Initiation and propagation","volume":"66","author":"Huang","year":"2006","journal-title":"Compos. Sci. Technol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2315","DOI":"10.1016\/S0266-3538(99)00083-4","article-title":"The influence of fibre properties of the performance of glass fiber reinforced polyamide 6,6","volume":"59","author":"Thomason","year":"1999","journal-title":"Compos. Sci. Technol."},{"key":"ref_32","first-page":"181","article-title":"Effect of fiber loading and fiber length on mechanical and thermal properties of short carbon fiber reinforced polypropylene composite","volume":"11","author":"Rezaei","year":"2007","journal-title":"Malays. J. Anal. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1016\/j.prostr.2017.07.159","article-title":"Effect of fiber length on the mechanical properties of high dosage carbon reinforced","volume":"5","author":"Capela","year":"2017","journal-title":"Procedia Struct. Integr."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1016\/j.indcrop.2017.07.020","article-title":"Hemp fiber reinforced thermoplastic polyurethane composite: An investigation in mechanical properties","volume":"108","author":"Haghighatnia","year":"2017","journal-title":"Ind. Crops Prod."},{"key":"ref_35","first-page":"872","article-title":"Fiber shortening during injection molding of glass fiber-reinforced phenolic molding compounds: Fiber length measurement method development and validation","volume":"60","author":"Maertens","year":"2021","journal-title":"Polym. Technol. Mater."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Faudree, M.C., Nishi, Y., and Salvia, M. (2022). Increasing Impact Strength of a Short Glass Fiber Compression Molded BMC by Shortening Fibers without Change in Equipment. Materials, 15.","DOI":"10.3390\/ma15031145"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"10768","DOI":"10.1016\/j.jmrt.2020.07.084","article-title":"Effect of hemp fiber length the mechanical and thermal properties of polypropylene\/SEBS\/hemp fiber composites","volume":"9","author":"Panaitescu","year":"2020","journal-title":"J. Mater. Res. Technol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"109719","DOI":"10.1016\/j.tws.2022.109719","article-title":"Effects of jute fiber length and weight percentage on quasi-static flexural and dynamic mechanical properties of jute\/polyester composites for thin-walled structure applications","volume":"179","author":"Senthilrajan","year":"2022","journal-title":"Thin-Walled Struct."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"10024","DOI":"10.1016\/j.crgsc.2021.100241","article-title":"Impact of fiber length on mechanical, morphological and thermal analysis of chemical treated jute fiber polymer composites for sustainable applications","volume":"5","author":"Sajin","year":"2022","journal-title":"Curr. Res. Green Sustain. Chem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"125304","DOI":"10.1016\/j.polymer.2022.125304","article-title":"Estimation of rheological percolation threshold and influence of fibre length on properties of polypropylene\/sisal fibre composites having near critical fibre length","volume":"258","author":"Bhagat","year":"2022","journal-title":"Polymer"},{"key":"ref_41","unstructured":"Aravinth, K., Sathish, R., Ramakrishnan, T., Balu Mahandiran, S., and Shiyam Sundhar, S. Mechanical investigation of agave fiber reinforced composites based on fiber orientation, fiber length, and fiber volume fraction, Mater. Today Proc., in press."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/S0921-5093(99)00277-4","article-title":"Shear lag models for discontinuous composites: Fibre end stresses and weak interface layers","volume":"270","author":"Starink","year":"1999","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_43","unstructured":"Bauccio, M.L. (1994). ASM Engineered Materials Reference Book, ASM International. [2nd ed.]."},{"key":"ref_44","unstructured":"(2024, February 23). Calcium Carbonate, Calcite (CaCO3). Available online: https:\/\/www.matweb.com\/search\/datasheet_print.aspx?matguid=bea4bfa9c8bd462093d50da5eebe78ac."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1016\/S1359-6462(01)01031-4","article-title":"Investigation of thermal residual stresses in tungsten-fiber\/bulk metallic glass matrix composites","volume":"45","author":"Dragoi","year":"2001","journal-title":"Scr. Mater."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.msea.2005.01.041","article-title":"Effects of WC size and amount on the thermal residual stress in WC\u2013Ni composites","volume":"398","author":"Seol","year":"2005","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_47","first-page":"581","article-title":"Overcoming the fragility of ceramics (Challenge to strengthen ceramics)","volume":"21","author":"Niihara","year":"1986","journal-title":"Ceram. Kyoujinka Fract. Toughness Ceram."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1016\/j.powtec.2021.09.027","article-title":"Influence of coarse grain particles on mechanical properties and fracture behavior in multi-modal Al-based metal matrix composites","volume":"394","author":"Wu","year":"2021","journal-title":"Powder Technol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1412","DOI":"10.2320\/matertrans.M2012145","article-title":"Effects of electron beam irradiation on Charpy impact value of short glass fiber (GFRP) samples with random distribution of solidification texture angles from zero to 90 degrees","volume":"53","author":"Faudree","year":"2012","journal-title":"Mater. Trans."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1924","DOI":"10.2320\/matertrans.MRA2007050","article-title":"Effects of Electron Beam Irradiation on Charpy Impact Value of GFRP","volume":"48","author":"Nishi","year":"2007","journal-title":"Mater. Trans."},{"key":"ref_51","unstructured":"James, A., and Lord, M. (1992). Macmillan\u2019s Chemical and Physical Data, London and Basingstoke, The Macmillan Press, Ltd."},{"key":"ref_52","unstructured":"Gordon, A., and Ford, R. (1972). The Chemists Companion\u2014A handbook of Practical Data, Techniques, and References, A Wiley Interscience Publication."},{"key":"ref_53","unstructured":"(2002). Standard Test Methods for Determining the Charpy Impact Resistance of Notched Specimens of Plastics (Standard No. ASTM D 6110-02)."},{"key":"ref_54","first-page":"396","article-title":"Schichtdickenabhangigkeit der warmerzeugungdurch elektronenbestrahlung im energiebereich zwischen 9 und 100 keV (Layer thickness dependency of heat generation by electron irradiation in the energy range between 9 and 100 keV)","volume":"23","author":"Christenhusz","year":"1967","journal-title":"Z. Angew. Phys."},{"key":"ref_55","unstructured":"(1991). Testing Method for Charpy Impact Strength of Carbon Fiber Reinforced Plastics (Standard No. JIS K 7077). (In Japanese)."},{"key":"ref_56","unstructured":"Splett, J., Iyer, H., Wang, C., and McCowan, C. (2008). National Institute of Standards and Technology (NIST) Recommended Practice Guide, Computing Uncertainty for Charpy Impact Test Machine Test Results, US Department of Commerce. Special publication 960-18."},{"key":"ref_57","unstructured":"Nishida, T., and Yasuda, E. (1986). Evaluation of Dynamic Properties of Ceramics (in Japanese, Ceramics no rikigaku tokusei hyouka), Nikkan Kogaku Shimbun Sha."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/9\/2036\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:34:07Z","timestamp":1760106847000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/9\/2036"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,4,26]]},"references-count":57,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2024,5]]}},"alternative-id":["ma17092036"],"URL":"https:\/\/doi.org\/10.3390\/ma17092036","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,4,26]]}}}