TY - JOUR AU - Drevet, Richard AU - Souček, Pavel AU - Mareš, Pavel AU - Ondračka, Pavel AU - Dubau, Martin AU - Kolonits, Tamás AU - Czigány, Zsolt AU - Balázsi, Katalin AU - Vašina, Petr TI - Aluminum tantalum oxide thin films deposited at low temperature by pulsed direct current reactive magnetron sputtering for dielectric applications JF - VACUUM J2 - VACUUM VL - 221 PY - 2024 PG - 15 SN - 0042-207X DO - 10.1016/j.vacuum.2023.112881 UR - https://m2.mtmt.hu/api/publication/34445377 ID - 34445377 AB - This research aims at studying aluminum tantalum oxide thin films (AlxTayOz) deposited at low temperature for dielectric applications. These ternary oxide layers are synthesized at 180 °C by physical vapor deposition (PVD), specifically the mid-frequency pulsed direct current reactive magnetron sputtering. The deposition process uses targets made of a mixture of aluminum and tantalum in various proportions. Four target compositions are studied containing 95 at.%, 90 at.%, 80 at.%, and 70 at.% of aluminum, corresponding to 5 at.%, 10 at.%, 20 at.%, and 30 at.% of tantalum, respectively. The ternary oxide thin films of AlxTayOz are compared to aluminum oxide (AlxOz) and tantalum oxide (TayOz) layers produced in the same experimental conditions. The AlxTayOz thin films are dense, uniform, and amorphous regardless of the experimental conditions used in this study. Their chemical composition changes as a function of the target composition. The oxygen flow used during deposition also affects the chemical composition of the oxide layers and the deposition rate. The oxide thin films with tantalum are deposited at higher deposition rates and contain more oxygen. Tantalum also promotes the amorphization of the oxide layers. The highest dielectric strength is measured for the thin film containing a low amount of tantalum combined with a high amount of oxygen. LA - English DB - MTMT ER - TY - JOUR AU - Furko, Monika AU - Detsch, Rainer AU - Horváth, Zsolt Endre AU - Balázsi, Katalin AU - Boccaccini, Aldo R. AU - Balázsi, Csaba TI - Amorphous, Carbonated Calcium Phosphate and Biopolymer-Composite-Coated Si3N4/MWCNTs as Potential Novel Implant Materials JF - NANOMATERIALS J2 - NANOMATERIALS-BASEL VL - 14 PY - 2024 IS - 3 PG - 16 SN - 2079-4991 DO - 10.3390/nano14030279 UR - https://m2.mtmt.hu/api/publication/34672527 ID - 34672527 LA - English DB - MTMT ER - TY - JOUR AU - Kaou, Maroua Houria AU - Furko, Monika AU - Ben Zine, Haroune Rachid AU - Balázsi, Katalin AU - Balázsi, Csaba TI - Morphological and structural evaluation of spark plasma sintered calcium silicate ceramics JF - INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY J2 - INT J APPL CERAM TEC VL - in press PY - 2024 SP - in press PG - 13 SN - 1546-542X DO - 10.1111/ijac.14684 UR - https://m2.mtmt.hu/api/publication/34555216 ID - 34555216 AB - Calcium silicate ceramics were successfully prepared at various temperatures by spark plasma sintering technique (SPS) using two different compositions, and their morphological and structural characteristics were thoroughly analyzed and compared by scanning electron microscope, X-ray diffraction, and apparent density measurements. The effect of the sintering method and temperature on microstructural properties has also been studied. The sintered samples prepared by SPS through a heat input of 800 degrees C showed the highest densification as results 800 degrees C was suggested as optimum sintering temperature. Different phases presented in pseudo-wollastonite, wollastonite, and triclinic Ca3(SiO4)O have been observed in the case of 50C50C with lowest porosity similar to 6%$\sim \;6\% $ and highest density 2.6 g/cm3, whereas the composition 10C90S resulted in a fully amorphous material presented in granular microstructure with density of 1.7 g/cm3.Schematic view of calcium silicate preparationimage LA - English DB - MTMT ER - TY - JOUR AU - Ženíšek, Jaroslav AU - Souček, Pavel AU - Ondračka, Pavel AU - Czigány, Zsolt AU - Buršíková, Vilma AU - Holec, David AU - Balázsi, Katalin AU - Vašina, Petr TI - Effect of Nb incorporation in Mo 2 BC coatings on structural and mechanical properties — Ab initio modelling and experiment JF - ACTA MATERIALIA J2 - ACTA MATER VL - 268 PY - 2024 PG - 12 SN - 1359-6454 DO - 10.1016/j.actamat.2024.119741 UR - https://m2.mtmt.hu/api/publication/34666828 ID - 34666828 LA - English DB - MTMT ER - TY - JOUR AU - Ben Zine, Haroune Rachid AU - Horváth, Zsolt Endre AU - Balázsi, Katalin AU - Balázsi, Csaba TI - Novel Alumina Dispersion-Strengthened 316L Steel Produced by Attrition Milling and Spark Plasma Sintering JF - COATINGS J2 - COATINGS VL - 13 PY - 2023 IS - 2 PG - 15 SN - 2079-6412 DO - 10.3390/coatings13020322 UR - https://m2.mtmt.hu/api/publication/33611439 ID - 33611439 AB - Alumina dispersion-strengthened 316L stainless steels were successfully produced using attrition milling and spark plasma sintering. Two different composites (316L/0.33 wt% and 316L/1 wt% Al2O3) were prepared by powder technology. The attrition milling produced a significant morphological transformation of the globular 316L starting powders and provided a homogeneous distribution of the nanosized alumina particles. The XRD results confirmed that the 316L steel was an austenitic γ-Fe3Ni2. The formation of a ferrite α-Fe phase was detected after milling; this was transformed to the austenitic γ-Fe3Ni2 after the sintering process. The addition of nanosized alumina particles increased the composites’ microhardness significantly to 2.25 GPa HV. With higher amounts of alumina, the nanosized particles tended to agglomerate during the milling process. The friction coefficient (FC) of the 316L/0.33 wt% Al2O3 and the 316L/1 wt% Al2O3 decreased because of the increase in the composite’s hardness; FC values of 0.96, 0.93 and 0.85, respectively, were measured respectively for the 316L reference, the 316L/0.33 wt% and the 316L/1 wt% Al2O3. The 316L/0.33 wt% Al2O3 composite had a higher flexural strength of 630.4 MPa compared with the 316L/1 wt% Al2O3 with 386.6 MPa; the lower value of the latter was related the agglomeration of the alumina powder during attrition milling. LA - English DB - MTMT ER - TY - JOUR AU - Drevet, Richard AU - Souček, Pavel AU - Mareš, Pavel AU - Dubau, Martin AU - Czigány, Zsolt AU - Balázsi, Katalin AU - Vašina, Petr TI - Multilayer thin films of aluminum oxide and tantalum oxide deposited by pulsed direct current magnetron sputtering for dielectric applications JF - VACUUM J2 - VACUUM VL - 210 PY - 2023 PG - 15 SN - 0042-207X DO - 10.1016/j.vacuum.2023.111870 UR - https://m2.mtmt.hu/api/publication/33599977 ID - 33599977 AB - This research describes the synthesis of multilayer thin films of aluminum oxide and tantalum oxide for dielectric applications. The multilayer thin films are made of two, four, or eight oxide layers produced by physical vapor deposition (PVD), specifically mid-frequency pulsed direct current magnetron sputtering. The oxide layers are stoichiometric Al2O3 and Ta2O5 with two specific morphologies observed from cross-section images obtained by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Al2O3 layers exhibit a columnar structure whereas the Ta2O5 layers are uniform and dense. However, the morphology of the Ta2O5 layers changes progressively in the four-layer and eight-layer systems under the influence of the morphology of the Al2O3 layer below. This behavior is induced by the morphological continuity of the interface between two oxide layers. X-ray diffraction (XRD) shows the low crystallinity of these oxide layers due to the experimental conditions used during the magnetron sputtering process, particularly the low deposition temperature. The dielectric behavior of the multilayer thin films is studied by dielectric strength measurements. The results are compared to the values obtained for single layers of Al2O3 and Ta2O5 produced under the same experimental conditions. The two-layer system shows an intermediate value compared to the single layers, higher than Al2O3 and lower than Ta2O5. The dielectric strengths of the four-layer and the eight-layer systems are higher than those measured for the single layers of Al2O3 and Ta2O5. Finally, the morphology and the crystallinity of the multilayer thin films are changed by thermal annealing of these samples at 850 °C under vacuum. The thermal annealing induces crystallization of the Ta2O5 layers and the loss of morphological continuity at the interface between the oxide layers. These modifications result however in a lower dielectric strength for all the multilayer thin films. LA - English DB - MTMT ER - TY - JOUR AU - Furko, Monika AU - Detsch, R. AU - Tolnai, István AU - Balázsi, Katalin AU - Boccaccini, A.R. AU - Balázsi, Csaba TI - Biomimetic mineralized amorphous carbonated calcium phosphate-polycaprolactone bioadhesive composites as potential coatings on implant materials JF - CERAMICS INTERNATIONAL J2 - CERAM INT VL - 49 PY - 2023 IS - 11 SP - 18565 EP - 18576 PG - 12 SN - 0272-8842 DO - 10.1016/j.ceramint.2023.02.231 UR - https://m2.mtmt.hu/api/publication/33767896 ID - 33767896 LA - English DB - MTMT ER - TY - JOUR AU - Furko, Monika AU - Balázsi, Katalin AU - Balázsi, Csaba TI - Calcium Phosphate Loaded Biopolymer Composites—A Comprehensive Review on the Most Recent Progress and Promising Trends JF - COATINGS J2 - COATINGS VL - 13 PY - 2023 IS - 2 PG - 30 SN - 2079-6412 DO - 10.3390/coatings13020360 UR - https://m2.mtmt.hu/api/publication/33649599 ID - 33649599 AB - Biocompatible ceramics are extremely important in bioengineering, and very useful in many biomedical or orthopedic applications because of their positive interactions with human tissues. There have been enormous efforts to develop bioceramic particles that cost-effectively meet high standards of quality. Among the numerous bioceramics, calcium phosphates are the most suitable since the main inorganic compound in human bones is hydroxyapatite, a specific phase of the calcium phosphates (CaPs). The CaPs can be applied as bone substitutes, types of cement, drug carriers, implants, or coatings. In addition, bioresorbable bioceramics have great potential in tissue engineering in their use as a scaffold that can advance the healing process of bones during the normal tissue repair process. On the other hand, the main disadvantages of bioceramics are their brittleness and poor mechanical properties. The newest advancement in CaPs doping with active biomolecules such as Mg, Zn, Sr, and others. Another set of similarly important materials in bioengineering are biopolymers. These include natural polymers such as collagen, cellulose acetate, gelatin, chitosan, and synthetic polymers, for example, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), and polycaprolactone (PCL). Various types of polymer have unique properties that make them useful in different fields. The combination of CaP particles with different biopolymers gives rise to new opportunities for application, since their properties can be changed and adjusted to the given requirements. This review offers an insight into the most up-to-date advancements in the preparation and evaluation of different calcium phosphate–biopolymer composites, highlighting their application possibilities, which largely depend on the chemical and physical characteristics of CaPs and the applied polymer materials. Overall, these composites can be considered advanced materials in many important biomedical fields, with potential to improve the quality of healthcare and to assist in providing better outcomes as scaffolds in bone healing or in the integration of implants in orthopedic surgeries. LA - English DB - MTMT ER - TY - JOUR AU - Kaou, Maroua Houria AU - Furko, Monika AU - Balázsi, Katalin AU - Balázsi, Csaba TI - Advanced Bioactive Glasses: The Newest Achievements and Breakthroughs in the Area JF - NANOMATERIALS J2 - NANOMATERIALS-BASEL VL - 13 PY - 2023 IS - 16 PG - 33 SN - 2079-4991 DO - 10.3390/nano13162287 UR - https://m2.mtmt.hu/api/publication/34093975 ID - 34093975 AB - Bioactive glasses (BGs) are especially useful materials in soft and bone tissue engineering and even in dentistry. They can be the solution to many medical problems, and they have a huge role in the healing processes of bone fractures. Interestingly, they can also promote skin regeneration and wound healing. Bioactive glasses are able to attach to the bone tissues and form an apatite layer which further initiates the biomineralization process. The formed intermediate apatite layer makes a connection between the hard tissue and the bioactive glass material which results in faster healing without any complications or side effects. This review paper summarizes the most recent advancement in the preparation of diverse types of BGs, such as silicate-, borate- and phosphate-based bioactive glasses. We discuss their physical, chemical, and mechanical properties detailing how they affect their biological performances. In order to get a deeper insight into the state-of-the-art in this area, we also consider their medical applications, such as bone regeneration, wound care, and dental/bone implant coatings. LA - English DB - MTMT ER - TY - JOUR AU - Kaou, Maroua Houria AU - Horváth, Zsolt Endre AU - Balázsi, Katalin AU - Balázsi, Csaba TI - Eco‐friendly preparation and structural characterization of calcium silicates derived from eggshell and silica gel JF - INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY J2 - INT J APPL CERAM TEC VL - 20 PY - 2023 IS - 2 SP - 689 EP - 699 PG - 11 SN - 1546-542X DO - 10.1111/ijac.14274 UR - https://m2.mtmt.hu/api/publication/33226841 ID - 33226841 LA - English DB - MTMT ER -