{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:06:12Z","timestamp":1785420372374,"version":"3.56.0"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2026,5,23]],"date-time":"2026-05-23T00:00:00Z","timestamp":1779494400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004504","name":"Research Council of Lithuania","doi-asserted-by":"publisher","award":["P-LU-24-46"],"award-info":[{"award-number":["P-LU-24-46"]}],"id":[{"id":"10.13039\/501100004504","id-type":"DOI","asserted-by":"publisher"}]},{"award":["P-LU-24-46"],"award-info":[{"award-number":["P-LU-24-46"]}],"id":[{"id":"https:\/\/ror.org\/02gs16m83","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007684","name":"Ministry of Education and Science of Ukraine","doi-asserted-by":"crossref","award":["M\/50-2024"],"award-info":[{"award-number":["M\/50-2024"]}],"id":[{"id":"10.13039\/501100007684","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The interaction of femtosecond laser ultrashort pulses with carbon fiber-reinforced polymer (CFRP) based on epoxy resin modified with different ratios of copper hydroxyapatite (Cu-HAp) and calcium hydroxyapatite (Ca-HAp) was investigated. Ablation efficiency was examined for two CFRP groups containing 1 wt% and 5 wt% Cu-HAp in the epoxy matrix, and in both cases, the maximum ablation efficiency was obtained at a fluence of about 6.4\u20137.5 J\/cm2. The corresponding energy-specific volumes were slightly higher for 1 wt% Cu-HAp (6.95 \u03bcm3\/\u03bcJ) and lower for 5 wt% Cu-HAp (6.26 \u03bcm3\/\u03bcJ), and at higher fluence, the ablation efficiency decreased smoothly, indicating a limited optimum fluence window for a given CFRP composition. A similar behaviour was observed for epoxy compounds containing 5 wt% total hydroxyapatite, both for Cu-HAp:Ca-HAp = 75:25 and 50:50 mixtures, which showed nearly identical maxima of energy-specific volume around 6.06 \u03bcm3\/\u03bcJ at 6.4 J\/cm2. Epoxy resin without carbon fibers, loaded with 1 wt% and 5 wt% Cu-HAp, exhibited higher energy-specific volumes of about 9\u201310 \u03bcm3\/\u03bcJ and 9\u201313 \u03bcm3\/\u03bcJ, respectively, at around 10 J\/cm2, followed by a decay of ablation efficiency at higher fluence. Finally, cutting and milling experiments on CFRP demonstrated acceptable surface quality and processing rates under femtosecond laser irradiation, confirming realistic prospects for advanced CFRP fabrication using optimized ablation conditions.<\/jats:p>","DOI":"10.3390\/polym18111284","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T00:30:33Z","timestamp":1779669033000},"page":"1284","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ablation of CFRP Modified with Copper and Calcium Hydroxyapatites by Femtosecond Laser Pulses for Further Material Cutting and Milling Applications"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9280-5919","authenticated-orcid":false,"given":"Paulius","family":"\u0160levas","sequence":"first","affiliation":[{"name":"Coherent Optics Laboratory, Optoelectronics Department, Center for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Orestas","family":"Ul\u010dinas","sequence":"additional","affiliation":[{"name":"Coherent Optics Laboratory, Optoelectronics Department, Center for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1692-0189","authenticated-orcid":false,"given":"Sergej","family":"Orlov","sequence":"additional","affiliation":[{"name":"Coherent Optics Laboratory, Optoelectronics Department, Center for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9812-6303","authenticated-orcid":false,"given":"Egidijus","family":"Vanagas","sequence":"additional","affiliation":[{"name":"Coherent Optics Laboratory, Optoelectronics Department, Center for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2818-8450","authenticated-orcid":false,"given":"Anna","family":"Bilousova","sequence":"additional","affiliation":[{"name":"Department of Chemical Technology of Composite Materials, Chemical Technology Faculty, Igor Sikorsky Kyiv Polytechnic Institute, Beresteiskyi Ave. 37, 03056 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6608-0117","authenticated-orcid":false,"given":"Denys","family":"Baklan","sequence":"additional","affiliation":[{"name":"Department of Chemical Technology of Composite Materials, Chemical Technology Faculty, Igor Sikorsky Kyiv Polytechnic Institute, Beresteiskyi Ave. 37, 03056 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0499-9491","authenticated-orcid":false,"given":"Oleksiy","family":"Myronyuk","sequence":"additional","affiliation":[{"name":"Department of Chemical Technology of Composite Materials, Chemical Technology Faculty, Igor Sikorsky Kyiv Polytechnic Institute, Beresteiskyi Ave. 37, 03056 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"034001","DOI":"10.1115\/1.4026526","article-title":"Machining of carbon fiber reinforced plastics\/polymers: A literature review","volume":"136","author":"Che","year":"2014","journal-title":"J. Manuf. Sci. Eng."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Wang, Z., Ma, Y., Yuan, B., Wu, C., Li, C., and Sun, S. (2023). Development of laser processing carbon-fiber-reinforced plastic. Sensors, 23.","DOI":"10.3390\/s23073659"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/j.msea.2005.08.064","article-title":"Carbon fiber reinforced plastics in aircraft construction","volume":"412","author":"Soutis","year":"2005","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Vijayan, D.S., Sivasuriyan, A., Devarajan, P., Stefa\u0144ska, A., Wodzy\u0144ski, \u0141., and Koda, E. (2023). Carbon fibre-reinforced polymer (CFRP) composites in civil engineering application\u2014A comprehensive review. Buildings, 13.","DOI":"10.3390\/buildings13061509"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"045010","DOI":"10.1088\/2631-6331\/ad8f8e","article-title":"Carbon fiber reinforced polymer (CFRP) laminates: Flexural strengthening method for prestressed concrete beams with anchorage loss","volume":"6","author":"Gebre","year":"2024","journal-title":"Funct. Compos. Struct."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1016\/j.conbuildmat.2017.08.031","article-title":"Behaviour of CFRC beams strengthened by FFRP laminates under static and impact loadings","volume":"155","author":"Wang","year":"2017","journal-title":"Constr. Build. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"128614","DOI":"10.1016\/j.surfcoat.2022.128614","article-title":"Preparation and performance of a composite epoxy coating based on modified hydroxyapatite","volume":"443","author":"Guo","year":"2022","journal-title":"Surf. Coat. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"120719","DOI":"10.1016\/j.biomaterials.2021.120719","article-title":"Carbon fiber reinforced polymers for implantable medical devices","volume":"271","author":"Chua","year":"2021","journal-title":"Biomaterials"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"510","DOI":"10.1016\/j.surneu.2004.01.025","article-title":"Prospective study on cranioplasty with individual carbon fiber reinforced polymere (CFRP) implants produced by means of stereolithography","volume":"62","author":"Wurm","year":"2004","journal-title":"Surg. Neurol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"109639","DOI":"10.1016\/j.compositesb.2022.109639","article-title":"Recent advances of interphases in carbon fiber-reinforced polymer composites: A review","volume":"233","author":"Zheng","year":"2022","journal-title":"Compos. Part B Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"100608","DOI":"10.1016\/j.xnsj.2025.100608","article-title":"Enhanced strength and durability of long fiber type carbon fiber reinforced plastic rods over titanium alloy rods for spinal fixation","volume":"22","author":"Morita","year":"2025","journal-title":"N. Am. Spine Soc. J. (NASSJ)"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1070","DOI":"10.1557\/mrc.2018.144","article-title":"Synthesis and applications of near-infrared absorbing additive copper hydroxyphosphate","volume":"8","author":"Darton","year":"2018","journal-title":"MRS Commun."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"560","DOI":"10.1016\/j.materresbull.2017.09.056","article-title":"Synthesis, characterization and catalytic properties of copper-substituted hydroxyapatite nanocrystals","volume":"97","author":"Othmani","year":"2018","journal-title":"Mater. Res. Bull."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"6661","DOI":"10.1039\/D4MA00603H","article-title":"Fabrication of composite scaffolds using hydroxyapatite, epoxy resin and silica for load-bearing applications","volume":"5","author":"Alam","year":"2024","journal-title":"Mater. Adv."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"16094","DOI":"10.1038\/s41598-020-73386-5","article-title":"Carbon fiber-reinforced pedicle screws reduce artifacts in magnetic resonance imaging of patients with lumbar spondylodesis","volume":"10","author":"Fleege","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"119946","DOI":"10.1016\/j.ijpharm.2020.119946","article-title":"Tailoring Cu substituted hydroxyapatite\/functionalized multiwalled carbon nanotube composite coating on 316L SS implant for enhanced corrosion resistance, antibacterial and bioactive properties","volume":"590","author":"Sivaraj","year":"2020","journal-title":"Int. J. Pharm."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/j.prro.2023.10.005","article-title":"Quantification of MRI artifacts in carbon fiber reinforced polyetheretherketone thoracolumbar pedicle screw constructs prior to spinal stereotactic radiosurgery","volume":"14","author":"Ghia","year":"2024","journal-title":"Pract. Radiat. Oncol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"317","DOI":"10.14245\/ns.2244920.460","article-title":"Carbon fiber-reinforced polyetheretherketone spinal implants for treatment of spinal tumors: Perceived advantages and limitations","volume":"20","author":"Haider","year":"2023","journal-title":"Neurospine"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"640","DOI":"10.3390\/surgeries5030051","article-title":"Calcium hydroxyapatite in its different forms in skin tissue repair: A literature review","volume":"5","author":"Cruel","year":"2024","journal-title":"Surgeries"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1511","DOI":"10.1007\/s13204-021-01813-8","article-title":"Noteworthy enhancement of wound-healing activity of triphala biomass metabolite-loaded hydroxyapatite nanocomposite","volume":"11","author":"Namasivayam","year":"2021","journal-title":"Appl. Nanosci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/j.ijbiomac.2021.03.085","article-title":"Preparation of nano-hydroxyapatite\/chitosan\/tilapia skin peptides hydrogels and its burn wound treatment","volume":"181","author":"Qianqian","year":"2021","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Sutha, M., Sowndarya, K., Chandran, M., Yuvaraj, D., Bharathiraja, B., and Praveen Kumar, R. (2017). Synthesis of value added biomimetic material of hydroxyapatite using aqueous calcareous fish wastes. Waste to Wealth, Springer.","DOI":"10.1007\/978-981-10-7431-8_3"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"4992","DOI":"10.1002\/pc.29287","article-title":"Research progress on laser processing of carbon fiber composite materials","volume":"46","author":"Zuo","year":"2025","journal-title":"Polym. Compos."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Jiang, H., Ma, C., Li, M., and Cao, Z. (2021). Femtosecond laser drilling of cylindrical holes for carbon fiber-reinforced polymer (CFRP) composites. Molecules, 26.","DOI":"10.3390\/molecules26102953"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"110741","DOI":"10.1016\/j.optlastec.2024.110741","article-title":"Experimental study on nanosecond laser thermal decomposition of CFRP and recycling of carbon fibers","volume":"175","author":"Ye","year":"2024","journal-title":"Opt. Laser Technol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Baklan, D., Myronyuk, O., Bilousova, A., \u0160levas, P., Minkevi\u010dius, J., Ul\u010dinas, O., Orlov, S., and Vanagas, E. (2025). Femtosecond Laser Ablation of Copper-Hydroxyphosphate-Modified CFRP. Materials, 18.","DOI":"10.20944\/preprints202509.1858.v1"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"20988","DOI":"10.1021\/acsomega.4c00148","article-title":"Controllable fabrication of hydrophilic surface micro\/nanostructures of CFRP by femtosecond laser","volume":"9","author":"Zuo","year":"2024","journal-title":"ACS Omega"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"13210","DOI":"10.1021\/acsapm.5c02689","article-title":"Fabrication of Superhydrophobic Carbon Fiber Composite Surfaces and Evaluation of Their Anti-Icing Performance under Static and Impacting Droplets","volume":"7","author":"Guo","year":"2025","journal-title":"ACS Appl. Polym. Mater."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"100082","DOI":"10.1016\/j.stlm.2022.100082","article-title":"Role of surface quality on biocompatibility of implants\u2014A review","volume":"8","author":"Pramanik","year":"2022","journal-title":"Ann. 3D Print. Med."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"4459","DOI":"10.2298\/TSCI2205459F","article-title":"Research progress on the quality and efficiency of carbon fiber reinforced thermoplastic polymer composites processed by laser","volume":"26","author":"Feng","year":"2022","journal-title":"Therm. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"\u0160levas, P., Minkevi\u010dius, J., Ul\u010dinas, O., Orlov, S., Vanagas, E., Bilousova, A., Baklan, D., and Myronyuk, O. (2025). An investigation of carbon-fiber-reinforced plastic ablation by femtosecond laser pulses for further material cutting. Coatings, 15.","DOI":"10.3390\/coatings15010104"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"112000","DOI":"10.1016\/j.compositesb.2024.112000","article-title":"Mechanism of selective texturing of CFRP by femtosecond laser","volume":"291","author":"Li","year":"2025","journal-title":"Compos. Part B Eng."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1007\/s12541-025-01365-9","article-title":"Femtosecond Laser Processing of Micro Textured CFRP Bonding Interfaces and their Adhesive Properties","volume":"27","author":"Li","year":"2025","journal-title":"Int. J. Precis. Eng. Manuf."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1007\/s41871-025-00254-z","article-title":"Micromachining of carbon fiber reinforced plastics using femtosecond pulsed laser","volume":"8","author":"Konishi","year":"2025","journal-title":"Nanomanuf. Metrol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"085001","DOI":"10.1063\/5.0208980","article-title":"Study on the processing characteristics of carbon fiber-reinforced plastics by ultra-short pulse laser","volume":"14","author":"Wu","year":"2024","journal-title":"AIP Adv."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/11\/1284\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T04:17:08Z","timestamp":1779682628000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/11\/1284"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,23]]},"references-count":35,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["polym18111284"],"URL":"https:\/\/doi.org\/10.3390\/polym18111284","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,23]]}}}