@article{MTMT:36289489,
	title = {Preparation and Analysis of High-Performance Thermoplastic Composites},
	url = {https://m2.mtmt.hu/api/publication/36289489},
	author = {Széplaki, Péter and Hajagos, Szabolcs and Krizsma, Szabolcs Gábor and Zink, Béla and Suplicz, András},
	doi = {10.1002/pc.70258},
	journal-iso = {POLYM COMPOSITE},
	journal = {POLYMER COMPOSITES},
	volume = {47},
	unique-id = {36289489},
	issn = {0272-8397},
	abstract = {As the plastics industry continues to grow, the amount of plastic waste increases. The European Union is trying to reduce the amount of plastic waste through various actions. Recycling is perhaps the best way to achieve this. The importance of polymer composites has increased dramatically, and thanks to the spread of thermoplastic resin transfer molding (T‐RTM), composites can be produced very efficiently. This is because ɛ‐caprolactam, the monomer of polyamide 6 (PA6), can be processed at low pressures like epoxy or any other thermoset resin due to its low viscosity. PA6 is produced from ɛ‐caprolactam, activator, and catalyst by in situ ring‐opening polymerization in a temperature‐controlled mold with sufficiently short cycle times. We produced carbon fiber–reinforced composite sheets with PA6 as the matrix material by T‐RTM. A special vertical injection molding machine and the corresponding in situ unit were used for the experiments. We investigated the mechanical, thermal, and morphological properties of continuous carbon fiber–reinforced composites—we performed mechanical and thermal tests on the samples and compared the results with the properties of reference sheets produced from the matrix material. Our goal was to produce high‐quality and properly impregnated composite products suitable for engineering applications. Exploring these relationships is essential for creating components with high aesthetic value, which can be used in visible locations in addition to their load‐bearing role.},
	keywords = {mechanical properties; thermal; injection molding; carbon fibers; Plastic products; Thermodynamic properties; thermal properties; PROPERTY; carbon fiber; Thermoplastics; Reinforced plastics; Molds; polyamide 6; Elastomers; Temperature measuring instruments; Plastic recycling; mechanical; Resin transfer molding; Thermoplastic composite; Plastics waste; Plastics industry; Resin-transfer molding; T-RTM technology; Molding technologies; Thermoplastic resin transfer molding technology},
	year = {2026},
	eissn = {1548-0569},
	pages = {1860-1871},
	orcid-numbers = {Hajagos, Szabolcs/0009-0008-8158-7400; Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Zink, Béla/0000-0002-7172-1484; Suplicz, András/0000-0002-0304-7491}
}

@article{MTMT:36455717,
	title = {An experimental and theoretical study on the electrical conductivity of polymer composites},
	url = {https://m2.mtmt.hu/api/publication/36455717},
	author = {Hajagos, Szabolcs and Kovács, József Gábor and Suplicz, András and Széplaki, Péter and Zink, Béla},
	doi = {10.1016/j.jmrt.2025.10.217},
	journal-iso = {J MATER RES TECHN},
	journal = {JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY},
	volume = {39},
	unique-id = {36455717},
	issn = {2238-7854},
	abstract = {In recent years, hydrogen fuel cells have emerged as one of the most promising green energy sources. Although fuel cells and their manufacturing technologies are still under development, recent research has shown encouraging progress. While polymers are typically known for their excellent electrical insulating properties, incorporating appropriate conductive fillers can transform them into electrically conductive composites. Potential fillers include graphite, graphene, carbon black, and carbon fibers. In this study, we evaluate the effect of filler properties on mechanical properties, and thermal and electrical conductivity in conductive mono-composites. Our results and conclusions can contribute to the development of conductive hybrid polymer composites suitable for fuel cell applications. We prepared composites using carbon black, carbon fiber, and graphite in a polypropylene matrix. We investigated the effects of processing parameters and evaluated the resulting materials' mechanical, thermal, and electrical properties. Among the tested fillers, one type of graphite exhibited superior electrical and thermal conductivity without compromising mechanical performance. Furthermore, we adapted a semi-empirical thermal conductivity model to describe the electrical conductivity of composites above the percolation threshold. The modified model showed high accuracy, offering a practical tool for material design and engineering applications. © © 2025. Published by Elsevier B.V.},
	keywords = {electric conductivity; theoretical study; Graphene; carbon fibers; thermal conductivity; Fuel cells; Carbon black; fuel cell; conducting polymers; Fillers; Hydrogen fuels; Electrical conductivity; Analytical Modeling; Analytical Modeling; Industrial research; Analytical models; Polymer matrix composites; Polymer composite; Manufacturing technologies; mechanical; Recent researches; conductive polymer composites; Conductive polymer composite; Hydrogen fuel cells; Green energy sources},
	year = {2025},
	eissn = {2214-0697},
	pages = {6300-6309},
	orcid-numbers = {Hajagos, Szabolcs/0009-0008-8158-7400; Kovács, József Gábor/0000-0002-7391-7085; Suplicz, András/0000-0002-0304-7491; Zink, Béla/0000-0002-7172-1484}
}

@article{MTMT:35656265,
	title = {Expanding the applicability of material jetting–printed photopolymer prototype injection moulds by gamma irradiation post-treatment},
	url = {https://m2.mtmt.hu/api/publication/35656265},
	author = {Krizsma, Szabolcs Gábor and Mészáros, László and Kovács, Norbert Krisztián and Suplicz, András},
	doi = {10.1016/j.jmapro.2024.12.037},
	journal-iso = {J MANUFACT PROCES},
	journal = {JOURNAL OF MANUFACTURING PROCESSES},
	volume = {134},
	unique-id = {35656265},
	issn = {1526-6125},
	abstract = {Additive manufacturing (AM) revolutionized modern production and tooling, as it can help speed up the development process. This is also true for injection moulding. For instance, polymeric low-volume injection moulds are easy to produce by material jetting (MJ) technologies like PolyJet™. The downside of these MJ printed moulds is their relatively low glass transition temperature, which can result in unacceptably low stiffness and increased creep compliance in the operational temperature range. Different post-curing techniques like high-energy irradiation can enhance the degree of cross-linking in MJ-printed photopolymer parts. We applied MJ (PolyJet™ technology) to produce specimens for mechanical and morphological characterizations and low-volume injection moulds. After printing, we subjected the specimens and the inserts to high-energy gamma irradiation with doses of 50 kGy, 100 kGy, 150 kGy and 200 kGy. Dynamic mechanical analysis (DMA) showed the effects of irradiation on material properties: the glass transition temperature of the photopolymer rose by almost 10 °C from 70.8 °C of the untreated insert to 81.6 °C of the specimen irradiated with 200 kGy. The creep time temperature superposition (TTS) tests proved that the increasing irradiation doses significantly reduced creep compliance, which resulted in considerably lower mould insert deformations. Creep compliance measured at 35 °C fell from 1920 μm2/N of the untreated specimen to 518 μm2/N of the specimen irradiated with 200 kGy. After the material tests, we applied an elaborated comprehensive state monitoring system (operational strain, cavity pressure and temperature measurements) to highlight the fundamental effect that the irradiation has on the operational behaviour of the MJ-printed mould inserts. Injection moulding tests showed that the increasing irradiation doses resulted in significantly decreased operational deformations. Maximal operational strain of the mould inserts fell from 1 % measured on the untreated (0 kGy) insert to 0.5 % measured on the insert irradiated with 200 kGy. It is highly desirable because product dimensional accuracy is also increased. Irradiation also significantly increased mould life (the number of products that can be manufactured), which is a crucial advantage from an economic point of view. We proved that post-curing by gamma radiation is a feasible way to enhance the applicability and the dimensional stability of photopolymer injection mould inserts. This is a definitely novel way to enhance the applicability of MJ-printed low-volume injection moulds.},
	year = {2025},
	eissn = {2212-4616},
	pages = {135-145},
	orcid-numbers = {Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Mészáros, László/0000-0001-5979-7403; Suplicz, András/0000-0002-0304-7491}
}

@article{MTMT:36144700,
	title = {Customised production of injection moulded parts from recycled materials using rapid tooling approach and coupled injection moulding-thermal and mechanical simulation},
	url = {https://m2.mtmt.hu/api/publication/36144700},
	author = {Krizsma, Szabolcs Gábor and Suplicz, András and Gere, Dániel},
	doi = {10.1016/j.rineng.2025.105272},
	journal-iso = {RESULT ENGIN},
	journal = {RESULTS IN ENGINEERING},
	volume = {26},
	unique-id = {36144700},
	issn = {2590-1230},
	abstract = {Additive manufacturing is the state of the art in modern tool making. It makes the low-volume production of polymeric parts and prototype moulds feasible. Injection moulded parts can be customised flexibly and fast with prototype polymeric moulds. Another trend in the plastics industry is the widespread use of recycled materials to reduce environmental impact. In this article, we introduce a novel technological concept: applying prototype injection moulds to process recycled materials. We investigated three materials: original PP, a recycled PP-HDPE mixture, which is a commercially available injection moulding material and a recycled PA6 that is difficult to mould due to the high melt temperature. All three materials were injection moulded successfully with outstanding product quality. The injection moulding process was modelled with a coupled injection moulding simulation—finite element thermal and mechanical simulation. The presented novel modelling method proved accurate. The injection pressure, temperature and strain results of the simulations showed excellent agreements with the measured results. The application of additively manufactured prototype moulds to produce parts from recycled materials is definitely a novelty.},
	year = {2025},
	eissn = {2590-1230},
	orcid-numbers = {Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Suplicz, András/0000-0002-0304-7491; Gere, Dániel/0000-0002-2808-2672}
}

@article{MTMT:36217662,
	title = {Novel Coupled Simulation Method and Comprehensive Metrology to Enhance the Application of Prototype Injection Moulds},
	url = {https://m2.mtmt.hu/api/publication/36217662},
	author = {Krizsma, Szabolcs Gábor and Suplicz, András},
	doi = {10.4028/p-q56eQa},
	journal-iso = {ADV SCI TECHNOL},
	journal = {ADVANCES IN SCIENCE AND TECHNOLOGY},
	volume = {165},
	unique-id = {36217662},
	issn = {1662-8969},
	abstract = {Injection moulding is the most diverse and dynamically developing polymer processing technology. Conventional injection moulding is economically viable only in large-volume part production. However, there is an ever-growing demand for more customised, low-volume plastic products, which is called mass customization. This need can be served by the hybridisation of injection moulding with additively manufactured, low-volume injection moulds (produced for example from thermoset resins by PolyJet technology). In our work, we elaborated a novel statemonitoring and modelling method to analyse the mechanical and thermal characteristics (strains and temperature distribution) of these polymeric injection mould inserts during operation. The results of the modelling method were successfully validated by the actual injection moulding experiments, proving the adequacy of the modelling method. © 2025 Trans Tech Publications Ltd, All Rights Reserved.},
	keywords = {Injection moulding; Rapid tooling; Coupled simulation; Additive manufacturing},
	year = {2025},
	eissn = {1662-0356},
	pages = {179-188},
	orcid-numbers = {Suplicz, András/0000-0002-0304-7491}
}

@{MTMT:36227425,
	title = {Novel Coupled Simulation Method and Comprehensive Metrology to Enhance the Application of Prototype Injection Moulds},
	url = {https://m2.mtmt.hu/api/publication/36227425},
	author = {Krizsma, Szabolcs Gábor and Suplicz, András},
	booktitle = {The 10th International Scientific Conference on Advances in Mechanical Engineering (ISCAME)},
	volume = {165 AST},
	unique-id = {36227425},
	abstract = {Injection moulding is the most diverse and dynamically developing polymer processing technology. Conventional injection moulding is economically viable only in large-volume part production. However, there is an ever-growing demand for more customised, low-volume plastic products, which is called mass customization. This need can be served by the hybridisation of injection moulding with additively manufactured, low-volume injection moulds (produced for example from thermoset resins by PolyJet technology). In our work, we elaborated a novel statemonitoring and modelling method to analyse the mechanical and thermal characteristics (strains and temperature distribution) of these polymeric injection mould inserts during operation. The results of the modelling method were successfully validated by the actual injection moulding experiments, proving the adequacy of the modelling method. © 2025 Trans Tech Publications Ltd, All Rights Reserved.},
	keywords = {Injection moulding; Rapid tooling; Coupled simulation; Additive manufacturing},
	year = {2025},
	pages = {393-402},
	orcid-numbers = {Suplicz, András/0000-0002-0304-7491}
}

@article{MTMT:36288262,
	title = {Comparative study of additively manufactured, state-of-the-art photopolymers and their applicability in prototype mould making},
	url = {https://m2.mtmt.hu/api/publication/36288262},
	author = {Krizsma, Szabolcs Gábor and Suplicz, András},
	doi = {10.1007/s00170-025-16286-0},
	journal-iso = {INT J ADV MANUFACT TECHNOL},
	journal = {INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY},
	volume = {139},
	unique-id = {36288262},
	issn = {0268-3768},
	abstract = {Additive manufacturing is a state-of-the-art technology widely used for mould making. Material jetting (MJ) is one of the best additive technologies because of the dimensional accuracy and the outstanding mechanical properties of the printed parts. MJ is a high-end additive technology, requiring expensive printers and resins. Because of this, MJ is typically limited to special, technical applications. Another limitation of MJ-printed resins is their low glass transition temperature ( T g ), and the decrease in strength, stiffness and high creep above T g . An important development direction of photopolymer resins is increasing the T g and enhancing resistance against heat. This article presents a thermal post-curing method, which aims to improve the thermomechanical performance of photopolymers. This article presents a comparative study of two commercial resins for injection mould making: DigitalABS and Loctite3955. The mechanical and thermomechanical properties of both resins can be modified after printing by thermal post-curing, which results in higher strength, stiffness and resistance against heat, and reduced creep, which are all beneficial for mould making. Thermomechanical material characterisation was performed first, to prove the effect of thermal post-curing on the temperature-dependent stiffness and creep properties. The temperature dependence of stiffness was measured by dynamic mechanical analysis in temperature sweep mode. Both as-printed resins showed a decrease in stiffness with increasing temperature but Loctite3955 post-cured above 160 °C, causing an increase in stiffness. Thermal post-curing drastically increased the storage modulus of Loctite3955 from 2041 to 3934 MPa at room temperature and the difference remained nearly the same in the 20–160 °C temperature range. Following the successful material tests, we performed injection moulding tests to analyse the effect of thermal post-curing on mould insert deformations. Thermal treatment resulted in a considerably (by more than 80%) reduced deformation of the mould insert made from Loctite3955 compared to DigitalABS. Also, there was no residual deformation on the post-cured Loctite3955 insert in contrast to the DigitalABS inserts, which had considerable deformations. The results presented in this article clearly highlight the beneficial effects of thermal post-treatment on the thermomechanical properties of photopolymer parts. Our findings allow the more widespread use of these photopolymers in applications where signifcant thermal and mechanical loads occur.},
	year = {2025},
	eissn = {1433-3015},
	pages = {6187-6200},
	orcid-numbers = {Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Suplicz, András/0000-0002-0304-7491}
}

@article{MTMT:36433223,
	title = {Applying high-performance resins in stereolitography printing to produce prototype injection moulds},
	url = {https://m2.mtmt.hu/api/publication/36433223},
	author = {Krizsma, Szabolcs Gábor and Suplicz, András},
	doi = {10.1038/s41598-025-23249-8},
	journal-iso = {SCI REP},
	journal = {SCIENTIFIC REPORTS},
	volume = {15},
	unique-id = {36433223},
	abstract = {Additive manufacturing (AM) revolutionised the modern plastics industry. Its flexibility and ability to build almost any complex geometry without the need for conventional tooling or machining is especially desirable. In our article, we analysed two resins which can be processed by vat photopolymerisation: High Temperature and Rigid10K. They are especially recommended for rapid tooling because of their resistance to heat loads, high strength and stiffness. The application of vat photopolymerisation to produce prototype injection moulds is a definite novelty because the international research community has not realised the potential of this AM technology in rapid tooling. We performed dynamic mechanical analysis in temperature sweep and creep time temperature superposition (TTS) modes to determine the temperature-dependent stiffness and creep characteristics of the resins. The storage modulus of the High Temp resin was 2960 MPa at room temperature while it was 4055 MPa for Rigid10K. Their difference in storage modulus gradually diminished as they were heated to 123 °C. Above that, the High Temp resin showed higher modulus. The creep compliance of Rigid10K was considerably lower compared to the High Temp resin until 90 °C but it was excessive above that. After the material tests, two injection mould inserts were printed and post-cured. The inserts were fitted with strain gauges and thermocouples, which measured the operational deformations and the temperature of the inserts during injection moulding. The Rigid10K insert showed nearly an order of magnitude lower maximum deformation than the High Temp insert. The Rigid10K insert endured the injection moulding test while the High Temp insert cracked. The results proved that both resins are applicable in prototype injection mould making, but the durability of the Rigid10K insert is considerably better.},
	year = {2025},
	eissn = {2045-2322},
	orcid-numbers = {Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Suplicz, András/0000-0002-0304-7491}
}

@article{MTMT:36455001,
	title = {Gamma-irradiation post-treatment in photopolymer-based additive manufacturing: An efficient method for improved performance},
	url = {https://m2.mtmt.hu/api/publication/36455001},
	author = {Krizsma, Szabolcs Gábor and Kiss, Lóránt and Suplicz, András and Homlok, Renáta and Mészáros, László},
	doi = {10.1016/j.mtcomm.2025.114205},
	journal-iso = {MATER TODAY COMMUN},
	journal = {MATERIALS TODAY COMMUNICATIONS},
	volume = {49},
	unique-id = {36455001},
	issn = {2352-4928},
	abstract = {Material-jetting is a sub-field of additive manufacturing that typically produces cross-linked products with high engineering value. Various post-treatment techniques are often used to enhance the performance of the product. The aim of these post-treatments is mainly to increase the cross-linking density. The use of ionising radiation can be an excellent alternative for this purpose. In this study, gamma radiation was chosen as the ionising radiation and its applicability as a post-treatment technique was investigated. The printed samples were post-treated with absorbed doses between 25 and 200 kGy. Irradiation has significantly changed the mechanical properties. The tensile modulus for the untreated sample (0 kGy) was 1.92 GPa and it increased to 2.76 GPa after irradiation with 200 kGy, while the tensile strength increased from 38.1 MPa to 64.6 MPa. The heat deflection temperature of the untreated specimen was 48 degrees C, which increased to 60 degrees C for the 200 kGy irradiated specimen. The irradiation also had an effect on the thermal properties: the glass transition temperature increased from 46.7 degrees C to 59.6 degrees C, which is an outstanding result when compared to other post-treatment techniques. The changes in properties were caused by an increase in cross-link density, as confirmed by swelling and Fourier transform infrared spectroscopic analyses. The results presented in this study prove that high-energy gamma irradiation is a novel and effective tool to customise the mechanical and thermal properties of material jetting printed photopolymer parts. Gamma irradiation has clear practical benefits in industries where it is already applied, like medical device manufacturing, pharmaceutical or food industry, where strict sterilisation requirements can often be fulfilled by it.},
	keywords = {Mechanical testing; gamma irradiation; CROSS-LINK DENSITY; Material jetting},
	year = {2025},
	eissn = {2352-4928},
	orcid-numbers = {Krizsma, Szabolcs Gábor/0000-0003-4574-7135; Suplicz, András/0000-0002-0304-7491; Mészáros, László/0000-0001-5979-7403}
}

@CONFERENCE{MTMT:36344317,
	title = {Overmoulding Strength of PP and ABS Systems: Influence of Tool and Melt Temperatures},
	url = {https://m2.mtmt.hu/api/publication/36344317},
	author = {Lorber, Rebeka and Zink, Béla and Suplicz, András and Krizsma, Szabolcs Gábor and Széplaki, Péter and Haar, Bernd and Lechner, Bernhard and Verčkovnik, Marko and Dobnik, Jure},
	booktitle = {Metal replacement and lightweight polymer composites : 3rd IPPT_TWINN conference},
	unique-id = {36344317},
	year = {2025},
	pages = {22-22},
	orcid-numbers = {Zink, Béla/0000-0002-7172-1484; Suplicz, András/0000-0002-0304-7491}
}