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Number of results: 66
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Abstract

This paper presents matters related to production of ceramic and cast iron composite. The composite was made with the use of a foam structured ceramic insert. The tests included measuring of hardness, impact strength and resistance to abrasive wear of the composite produced. On the basis of obtaining results was stated that the use of foamed ceramic filters provides good conditions of filling a ceramic framework with molten grey or chromium cast iron. The growth of hardness of the ceramic- grey cast iron composite is ca. 60% as compared to the grey cast iron hardness. The growth of hardness of the ceramic- chromium cast iron composite is slight and does not exceed 5 % in comparison to the chromium cast iron. Introduction of the ceramic inserts deteriorates the cast iron impact strength by ca. 20 - 30 %. The use of ceramic inserts increases the resistance to abrasive wear in case of grey cast iron by ca. 13% and in case of the chromium cast iron by ca. 10 %.
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Authors and Affiliations

A. Dulska
A. Studnicki
M. Cholewa
J. Szajnar
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Abstract

In the work five ceramic compounds based on the (K0.44Na0.52Li0.04)NbO3 (KNLN) material modified with oxides: Cr2O3, ZnO, Sb2O3 or Fe2O3 (in an amount of 0.5 mol.%) were obtained. The KNLN-type composition powder was prepared by solid phase synthesis from a mixture of simple oxides and carbonates, while compacted of the ceramic samples was conducted by free sintering methods. In the work the effect of the used admixture on the electrophysical properties of the KNLN ceramics was presented. The XRD, EDS tests, the SEM measurements of the morphology ceramic samples, dielectric properties and DC electric conductivity were conducted. The research showed that the used admixtures introduced into the base of KNLN-type composition improve the microstructure of the ceramic samples and improve their sinterability. In the case of the dielectric measurements, it was observed a decrease in the maximum dielectric permittivity at the TC for dopred KNLN-type samples. The addition of an admixture of chromium, zinc, antimony or iron in an amount of 0.5 mol.% to the base composition (K0.44Na0.52Li0.04)NbO3 practically does not change the phase transition temperature. The diminution in the density value of doped KNLN ceramics was attributed to the alkali elements volatilization.

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Authors and Affiliations

D. Bochenek
K. Osińska
P. Niemiec
M. Adamczyk
T. Goryczka
R. Szych
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Abstract

Clay was admixtured with 1, 2, 3 and 10% of waste sludge precipitated from lead electroplating fluoroborate electrolyte. The sludge contained, besides 60.7% of lead, 3.7% of fluorine. Small standardized ceramic bricks were burnt at 980°C and then tested for physical and mechanical features (contraction, water soaking, freeze resistance, compressive strength) and for leaching with water saturated with carbon dioxide. The tests showed that 1% of added sludge did not change properties of ceramic bricks and leaching of lead and fluorine is not hazardous, while the larger admixtures result in spoiling of quality features. On burning fluorine is emitted to exhaust gases.
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Authors and Affiliations

Tadeusz Stefanowicz
Małgorzata Osińska
Stefania Napieralska-Zagozda
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Abstract

The paper presents mathematic-statistic methods defining the influence of stress on ceramic elements’ durability of hip and knee joints endoprostheses. The tests were conducted with Finite Elements Method in the ADINA System. The obtained results state the influence of load on the values of durability and stress, that get formed in ceramic parts of joints, and help to detect and solve technical problems and thus, counteract the subsequent effects resulting from premature wear of endoprosthesis elements. The paper emphasizes necessity of discovering new materials, that will be bio-compliant and wear resistant. Although ceramic materials like Al2O3, ZrO2, are brittle and less resistant to load than metallic implants, their improving mechanical parameters (excellent tribological properties), make them becoming new standard in biomaterials for clinical use. That opens new possibilities especially for hip or knee joints alloplasty.
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Authors and Affiliations

M. Nabrdalik
1
ORCID: ORCID
M. Sobociński
1
ORCID: ORCID

  1. Czestochowa University of Technology, Faculty of Mechanical Engineering and Computer Science, Department of Technology and Automation, 21 Armii Krajowej Av., 42-201 Czestochowa, Poland
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Abstract

The paper presents selected granular ceramic materials available on the Polish market. Their characteristics have been determined in the aspect on application in the production of iron alloy-ceramic composite. The possibility of obtaining a composite layer by means of bulk grains in molds of plates were considered, which was the foundation for experimental molds to be used in service tests. On the basis of obtaining results was stated that the knowledge of the characteristics of bulk grains enables the calculation of their quantity necessary for the composite production. When using the bulk grains the thickness of the composite layer is restricted by the thermal relations (cooler) and the physical phenomena (buoyancy, metal static pressure). Increasing amount of grains above definite condition causes surface defects in the castings. Each casting, due to its weight, shape and place of composite layer production requires an individual approach, both at the stage of formation and that of calculation of the required quantity of ceramic grains.
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Authors and Affiliations

A. Dulska
J. Kilarski
A. Studnicki
J. Szajnar
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Abstract

The paper reports the consequences of lanthanum modifications of barium bismuth niobiate (BaBi2Nb2O9) ceramics. The discussed materials were prepared by solid state synthesis and a one-step sintering process. The investigations are focused on dielectric aspects of the modification. The presented results reveal that the trivalent lanthanum ions incorporate twovalent barium ions, which is connected with the creation of A-site cationic vacancies as well as oxygen vacancies. Such a scenario results in significant decreasing in grain boundaries resistivity. The activation energy of grain boundaries conductivity is significantly reduced in the case of lanthanum admixture.

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Authors and Affiliations

M. Adamczyk-Habrajska
ORCID: ORCID
T. Goryczka
ORCID: ORCID
D. Szalbot
ORCID: ORCID
J. Dzik
ORCID: ORCID
M. Rerak
D. Bochenek
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Abstract

Preliminary tests aimed at obtaining a cellular SiC/iron alloy composite with a spatial structure of mutually intersecting skeletons, using a

porous ceramic preform have been conducted. The possibility of obtaining such a composite joint using a SiC material with an oxynitride

bonding and grey cast iron with flake graphite has been confirmed. Porous ceramic preforms were made by pouring the gelling ceramic

suspension over a foamed polymer base which was next fired. The obtained samples of materials were subjected to macroscopic and

microscopic observations as well as investigations into the chemical composition in microareas. It was found that the minimum width of a

channel in the preform, which in the case of pressureless infiltration enables molten cast iron penetration, ranges from 0.10 to 0.17 mm. It

was also found that the ceramic material applied was characterized by good metal wettability. The ceramics/metal contact area always has

a transition zone (when the channel width is big enough), where mixing of the components of both composite elements takes place.

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Authors and Affiliations

M. Cholewa
B. Lipowska
B. Psiuk
Ł. Kozakiewicz
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Abstract

A short literature survey which justifies coating of ceramic cutting inserts is presented. The results reported are on selected nitride

coatings, in particular nanoscale multilayer, with layers of type Ti-Zr-N, TiN, ZrN and (TiAl)N, deposited by the arc PVD method on oxidecarbide ceramic cutting inserts of type TACN and TW2 produced at the Institute of Advanced Manufacturing Technology. Measurements and quality assessments were made, including of thickness of the coatings and of their constituent micro and nanolayers, microhardness of the coating and of the substrate, surface roughness of the inserts and of the cylindrical workpieces turned with these tools. Lifetimes of the coated and uncoated inserts were compared in turning an alloy tool steel. A significant increase in lifetime of the coated TW2 cutting tools was shown.

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Authors and Affiliations

K. Czechowski
I. Pofelska-Filip
B. Królicka
P. Szlosek
B. Smuk
J. Wszołek
A. Kurleto
J. Kasina
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Abstract

The paper presents the test results for the microstructure of ZnO varistors comprising high voltage gapless surge arresters. The tests were performed on varistors produced in different periods and by various manufacturers. The research was inspired by different characteristics of changes in values of current flowing through surge arresters as a function of changes in values of system voltage in a 220 kV substation, and the temperature in a multi-year cycle. Furthermore, the effects of varistor microstructure degradation following a failure of an unsealed surge arrester were investigated. The results provided the grounds for assessment of ZnO varistor microstructure parameters in terms of their durability and resistance to degradation processes.

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Authors and Affiliations

P. Papliński
J. Wańkowicz
P. Ranachowski
Z. Ranachowski
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Abstract

The rocks quarried in the neighboring Rutki and Ligota Tułowicka deposits (vicinity of Niemodlin) represent a single petrographic variety of basalt, i.e. nephelinite. The presence of nepheline (the mineral belonging to the group of feldspathoids) that forms the light-colored component of the groundmass is the characteristic feature of these rocks. Nepheline is accompanied by fine crystals of pyroxene and, occasionally, magnetite. Distinctly larger pyroxene and olivine phenocrysts are dispersed within the groundmass. Neither minerals of the groundmass nor the phenocrysts of the pyroxenes reveal any signs of chemical weathering. However, such alterations are clearly visible in the phenocrysts of olivine. The basalt raw materials of both deposits are utilized mainly for the production of various assortments of crushed road aggregates and as components of concretes. These applications require the aggregates with the grain sizes >2 mm. There is also a possibility to utilize coarse-grained basalt aggregates for the manufacturing of rock wool. This is due to a favorable property of the rocks from Rutki and Ligota Tułowicka that is their relatively low content of magnetite resulting in the low capability of the molten basalt to crystallize. The chemical weathering of the olivine phenocrysts have proceeded toward the formation of clay minerals, among which those of the smectite group prevail. Their elevated quantities occur in the finest aggregate assortment, i.e. 0–0.85 mm. The fineness of this grain fraction and its elevated quantity of clay minerals are two favorable features to utilize this part of the basalt aggregate by the heavy clay industry as an additive improving the physico-mechanical parameters and providing the required red color of ceramic products..

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Authors and Affiliations

Piotr Wyszomirski
Tadeusz Szydłak
Tomasz Zawadzki
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Abstract

Using intelligent materials and sensors to monitor the safety of concrete structures is a hot topic in the field of civil engineering. In order to realize the omni-directional monitoring of concrete structural damage, the authors of this paper designed and fabricated an embedded annular piezoelectric ultrasonic sensor using the annular piezoelectric lead zirconate titanate (PZT) ceramic as a sensing element and epoxy resin as the matching and the backing layers. The influence of different matching and backing layers thickness on the acoustic characteristic parameters of the sensor were studied. The results show that the resonant frequency corresponding to the axial mode of annular piezoelectric ceramics moves toward the high frequency direction with the decrease of the height of piezoelectric ceramics, and the radial vibration mode increases as well as the impedance peak. With the thickness of the backing layer increases from 1 mm to 2 mm, the radial resolution of the annular piezoelectric ultrasonic sensor is enhanced, the pulse width is reduced by 39% comparing with the sensors which backing layer is 1 mm, and the head wave amplitude and −3 dB bandwidth are increased by 61% and 66%, respectively. When the matching layer thickness is 3 mm, the sensor has the highest amplitude response of 269 mV and higher sensitivity.
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Authors and Affiliations

Haoran Li
1
Yan Hu
2
Laibo Li
1
Dongyu Xu
2 3

  1. Shandong Provincial Key Lab of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, PR China
  2. School of Civil Engineering, Central South University, Changsha 410075, PR China
  3. School of Civil Engineering and Architecture, Linyi University, Linyi 276000, PR China
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Abstract

In this case ceramic layers from Metco ZrO2 and Al2O3 powders mixture (25/75; 50/50 and 75/25) were obtained through atmospheric plasma spraying (APS) after five passes on low carbon steel substrate. The sample surfaces mechanically grinded (160-2400) before and after ceramic layer deposition. Powder’s mixtures and the surface of ceramic thin layers were analyzed through: scanning electron microscopy (SEM). In order to understand the effect of surface wettability of the ceramic layers, before and after grinding the surface, three different liquids were used. Experimental results confirm the modification of the steel substrate surface characteristic from hydrophilic to hydrophobic when the ceramic layer was deposited. Surface free energy of hydration increases for all the samples with zirconia percentage addition before polishing process.
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Authors and Affiliations

M. Luțcanu
1 2
ORCID: ORCID
M. Coteață
3
ORCID: ORCID
M.A. Bernevig
1
ORCID: ORCID
C.D. Nechifor
2
ORCID: ORCID
M.M. Cazacu
2
ORCID: ORCID
P. Paraschiv
4
ORCID: ORCID
B. Istrate
5
ORCID: ORCID
G. Bădărău
1
ORCID: ORCID
I.G. Sandu
1
ORCID: ORCID
N. Cimpoeșu
1
ORCID: ORCID

  1. Gheorghe Asachi Technical University of Iasi, Faculty of Materials Science and Engineering, Prof.dr.doc. D. Mangeron no. 41 Street, 700050 Iasi, Romania
  2. "Gheorghe Asachi” Technical University of Iasi, Department of Physics, 700050 Iasi, Romania
  3. Gheorghe Asachi Tech Univ Iasi, Dept Machine Mfg Technol, 59A D Mangeron Blvd, Iasi 700050, Romania
  4. “Gheorghe Asachi” Technical University of Iasi, Department of Sport, 700050 Iasi, Romania
  5. Gheorghe Asachi Tech Univ Iasi, Fac Mech Engn 43 D Mangeron St, Iasi 700050, Romania
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Abstract

The subject of the work are modern composite materials with increased wear resistance intended for elements of machines operating in difficult conditions in the construction and mining industries. The study determined the effect of zone reinforcement of GX120Mn13 cast steel with macroparticles (Al 2O 3+ZrO 2) on the corrosion resistance and abrasion wear of the composite thus obtained. SEM studies have shown that at interface between two phases, and more precisely on the surface of particles (Al 2O 3+ZrO 2) a durable diffusion layers are formed. During the corrosion tests, no significant differences were found between the obtained parameters defining the corrosion processes of GX120Mn13 cast steel and GX120Mn13 with particles (Al 2O 3+ZrO 2) composite. No intergranular corrosion was observed in the matrix of the composite material, nor traces of pitting corrosion at both phases interface. This is very important in terms of tested material’s service life. Reinforcement of cast steel with particles (Al 2O 3+ZrO 2) resulted in a very significant improvement in the abrasion resistance of the composite – by about 70%. After corrosion tests, both materials were subjected to further operational investigations. These examinations consisted in determining the impact of corrosion processes on the durability of the composite in terms of abrasion. The obtained results indicate that corrosion processes did not significantly deteriorate the wear resistance of both the cast steel and the composite.
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Bibliography

[1] Uetz, H. (1986). Abrasion and Erosion. Munich–Vienna: Carl Hanser Verlag Publ.
[2] Hebda, M., Wachal, A. (1980). Trybology. Warsaw: Scientific and Technical Publ (in Polish).
[3] Kalandyk, B., Zapała, R., Kasińska, J. & Madej, M. (2021). Evaluation of microstructure and tribological propertiesof GX120Mn13 and GX120MnCr18-2 cast steels. Archives of Foundry Engineering. 21(4), 67-76. DOI: 10.24425/afe.2021.138681.
[4] Marcus, P. (2017). Corrosion mechanisms in theory and practice. London–New York: CRC Press.
[5] Podrzucki, C. (1991). Cast iron. Structure, properties, application. vol. 2. Krakow: ZG STOP Publ (in Polish).
[6] Kaczmar, J., Janus, A., Samsonowicz, Z. (1998). Influence of technological parameters on the production of selected parts of machines reinforced with ceramic fibers. Report of Institute of Machine and Automation Technology, Wroclaw University of Science and Technology, Series SPR, 35 (in Polish). [7] Kurzawa, A., Kaczmar, J.W. & Janus, A. (2008). Selected mechanical properties of aluminum composite materials reinforced with SiC particles. Archives of Foundry Engineering. 8(2), 99-102.
[8] Kaczmar, J.W. & Kurzawa, A. (2012). The effect of α-alumina particles on the properties of EN AC-44200 Al alloy based composite materials. Journal of Achievements in Materials and Manufacturing Engineering. 55(1), 39-44.
[9] Jach, K., Pietrzak K., Wajler, A., Sidorowicz, A. & Brykała, U. (2013). Application of ceramic preforms to the manufacturing of ceramic – metal composites. Archives of Metallurgy and Materials, 58(4), 1425-1428. DOI: 10.2478/amm-2013-0188.
[10] Gawroński, J., Szajnar, J. & Wróbel, P. (2004). Study on theoretical bases of receiving composite alloy layers on surface of cast steel castings. Journal of Materials Processing Technology. 157, 679-682. DOI: 10.1016/j.jmatprotec.2004.07.153.
[11] Szajnar, J., Walasek, A., & Baron, C. (2013). Tribological and corrosive properties of the parts of machines with surface alloy layer. Archives of Metallurgy and Materials. 58(3), 931-936. DOI: 10.2478/amm-2013-0104.
[12] Hryniewicz, T., Rokosz, K. (2010). Theoretical basis and practical aspects of corrosion. Koszalin: Publ. House of Koszalin University of Technology (in Polish).
[13] Medyński, D. & Chęcmanowski, J. (2022). Corrosion resistance of L120G13 steel castings zone-Reinforced with Al2O3. Materials. 15(12), 4090, 1-14. https://doi.org/10.3390/ma15124090.
[14] Song, Y., Jiang, G., Chen, Y., Zhao, P. & Tian, Y. (2017). Effects of chloride ions on corrosion of ductile iron and carbon steel in soil environments. Scientific Reports. 7, 6865, 1-13. https://doi.org/10.1038/s41598-017-07245-1.

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Authors and Affiliations

Daniel Medyński
1
ORCID: ORCID

  1. Witelon Collegium State University, Poland
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Abstract

In this paper the current status of microplasma devices and systems made in the LTCC technology is presented. The microplasma characteristics and applications are described.We discuss the properties of the LTCC materials, that are necessary for reliable operation of the sources. This material is well known for its good reliability and durability in harsh conditions. Still, only a few examples of such microplasma sources are described. Some of them have been developed by the authors and successfully used for chemical analysis and synthesis.

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Authors and Affiliations

Jan Macioszczyk
Leszek Golonka
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Abstract

Control of reaction conditions, short residence times and completely inert surfaces are of major importance when studying aging mechanisms by soot formation. The use of ceramics as reactor material in combination with a special reactor design allows control over industrially relevant reaction conditions (T max = 1100 °C, t Residence = 50 ms) and sample shapes while avoiding interfering side reactions. We have successfully tested new ceramic kinetic reactors in two model systems of propane dehydrogenation and reactor coil material. The presented reactor setup allows long-term measurements with industrially relevant material samples under controlled conditions. In both model reactions it was possible to perform studies on regeneration methods by oxidation and to study the effects on the material using different in-situ and ex-situ techniques including 31 P MAS NMR measurements.
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Authors and Affiliations

Jörn H. Matthies
1
Daniel Dittmann
2
ORCID: ORCID
Michael Dyballa
2
ORCID: ORCID
Ulrich Nieken
1
ORCID: ORCID

  1. University of Stuttgart, Institute of Chemical Engineering, Germany
  2. University of Stuttgart, Institute of Technical Chemistry, Germany
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Abstract

La0,7Ca0,3MnO3 polycrystalline were synthesized from La2O3, CaO and MnO2 powder mixture using a solid state reaction technique. The compound powders were obtained through the free sintering method at different temperatures and sintering times in order to study the influence of technological conditions on Ca doped La manganites. The most important physical features as structure, microstructure and morphology were described after X-ray diffraction investigation. Photographs of the specimen fractures were taken with SEM (scanning electron microscope) and they revealed high porosity of the tested material and great tendency for its grains to create agglomerates. Influence of doping and technological conditions on lattice parameters were studied by means of Rietvield analysis. The XRD measurements reveal that La0,7Ca0,3MnO3 has orthorhombic symmetry with Pnma space group.

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Authors and Affiliations

M. Bara
J. Dzik
ORCID: ORCID
K. Feliksik
L. Kozielski
B. Wodecka-Duś
ORCID: ORCID
T. Goryczka
ORCID: ORCID
A. Zarycka
M. Adamczyk-Habrajska
ORCID: ORCID
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Abstract

This paper describes preparation methodology and research results of newly developed materials from post-production fibrous waste that are resistant to high temperatures. Widely available raw materials were used for this purpose. Such approach has significant impact on the technological feasibility and preparation costs. Obtained materials were verified via applying of various tests including characterization of shrinkage, porosity, density and water absorption as well as X-ray analysis (XRD), followed by mechanical bending and compressive strength determination.

Based on the research results, the possible applications of materials as thermal insulators were indicated.

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Authors and Affiliations

K. Kogut
K. Kasprzyk
R. Kłoś
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Abstract

The amount of waste from washing dolomite aggregates increases continuously. Aggregates are washed to remove clayey pollutants.They consist of a large amount of clay minerals and carbonates. Their properties and amount depends on the type of raw material and type of washing technology. Utilization of waste from washing aggregates is common problem and has not been sought out yet. Their usage as the raw material in ceramics might be environmentally friendly way to utilize them.

This paper presents technological properties, phase composition and microstructure analysis of materials made of waste sludge from washing dolomite aggregates. Research was divided into three parts: technological properties analysis, phase composition analysis and microstructure analysis.

Samples made of waste dolomite sludge were formed in laboratory clay brick vacuum extruder and fired at 900, 1000 and 1100°C. For final materials, apparent density, open porosity, water absorption, compressive strength and durability were examined. Results of technological research suggest the possibility of the application of the waste sludge from washing aggregates in building ceramics technology as bricks materials. Waste sludge from washing dolomite aggregates can be used as the main raw material of building ceramics masses. Without any additional technological operations (e.g. drying or grinding), the material with satisfactory properties was obtained. According to durability results all obtained materials can be used for masonry protected against water penetration and without contact with soil and ground water and also for masonry subjected to passive exposure (F0 – according to the standard EN 771-1).

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Authors and Affiliations

Ewelina Kłosek-Wawrzyn
Grzegorz Łój
Anna Bugaj
Wojciech Wons
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Abstract

The paper presents results of investigation of microstructure and micro-hardness for material of ZnO varistors applied to 110 kV surge arrester and surge arrester counter. The research combined two pairs of varistors, each consisted of one varistor subjected before to operation, while the other one was brand new unit and constituted a reference. All varistors were made of the same material by the reputable manufacture. The tests revealed a different degree of the material degradation for varistors subjected before to operation. This also refers to different degradation mechanism observed for the material of these varistors, if typical effects of degradation of aged ZnO varistors were considered as a reference. Physical state of spinel in the microstructure had a significant impact on the material degradation, however a considerable loosening of the microstructure associated with bismuth oxide was observed too. It was surprising, since the precipitates of the bismuth oxide phase most often showed very good binding to the ZnO matrix and high resistance to associated electrical, thermal and mechanical effects. The degradation effects in the ZnO matrix proved to be limited only.

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Authors and Affiliations

P. Papliński
J. Wańkowicz
H. Śmietanka
P. Ranachowski
Z. Ranachowski
ORCID: ORCID
S. Kudela Jr
M. Aleksiejuk
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Abstract

The paper presents investigations of microstructure of varistors of damaged surge arrester counters. A similar ZnO varistor, not subjected before to operation, was a point of reference in this research. The results of investigations of the ZnO varistors show an untypical phase composition of their material, which was characterized by unsatisfying homogeneity and cohesion. The degradation processes of varistor material in the subsequent stages were recognized and described. A harmful impact of humidity inside the untight surge arrester counter on its operation and its ZnO varistors was proved. Some conclusions being the result of the operation checking of surge arrester counters were presented too.

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Authors and Affiliations

P. Papliński
J. Wańkowicz
P. Ranachowski
Z. Ranachowski
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Abstract

Al and Nb-doped Li7La3Zr2O12 (LLZO) and W-doped LLZO lithium ion conducting electrolyte samples were prepared and their H2O stability was investigated. The LLZO samples were exposed to 50% humidified air for 48 h. After H2O exposure, a cubic to tetragonal transformation occurred and acquired SEM images exhibited the presence of reaction phases at the grain boundaries of Al and Nb-LLZO. As a result, the lithium ion conductivity significantly decreased after H2O exposure. On the contrary, W-LLZO showed good stability against H2O. Although the cubic to tetragonal transformation was also observed in H2O-exposed W-LLZO, the decrease in lithium ion conductivity was found to be modest. No morphological changes of the W-LLZO samples were confirmed in the H2O-exposed W-LLZO samples.

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Authors and Affiliations

Eun-Jeong Yi
Keun-Young Yoon
Hyun-Ah Jung
Haejin Hwang
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Abstract

Investigations on integration of optoelectronic components with LTCC (low temperature co-fired ceramics) microfluidic module are presented. Design, fabrication and characterization of the ceramic structure for optical absorbance is described as well. The geometry of the microfluidic channels has been designed according to results of the CFD (computational fluid dynamics) analysis. A fabricated LTCC-based microfluidic module consists of an U-shaped microchannel, two optical fibers and integrated light source (light emitting diode) and photodetector (light-to-voltage converter). Properties of the fabricated microfluidic system have been investigated experimentally. Several concentrations of potassium permanganate (KMnO4) in water were used for absorbance/transmittance measurements. The test has shown a linear detection range for various concentrations of heavy metal ions in distilled water. The fabricated microfluidic structure is found to be a very useful system in chemical analysis.

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Authors and Affiliations

Karol Malecha
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Abstract

In the paper the modelling of thermo-mechanical effects in the process of friction welding of corundum ceramics and aluminium is presented. The modelling is performed by means of finite element method. The corundum ceramics contains 97% of Al2O3. The mechanical and temperature fields are considered as coupled fields. Simulation of loading of the elements bonded with the heat flux from friction heat on the contact surface is also shown. The heat flux was modified in the consecutive time increments of numerical solutions by changeable pressure on contact surface. Time depending temperature distribution in the bonded elements is also determined. The temperature distribution on the periphery of the cylindrical surfaces of the ceramics and Al was compared to the temperature measurements done with a thermovision camera. The results of the simulation were compared to those obtained from the tests performed by means of a friction welding machine

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Authors and Affiliations

Z. Lindemann
K. Skalski
W. Włosiński
J. Zimmerman

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