Pub Date : 2023-08-28DOI: 10.1080/17436753.2023.2247682
Dewei Cui, Hui Shao
ABSTRACT In this study, undoped and Sr2+ doped BaZrO3 ceramics were prepared by solid-state reaction using 3 wt-% B2O3 as sintering aid. The phase composition and microstructure of BaZrO3 were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that introducing an appropriate amount of Sr2+ makes BaZrO3 ceramics Q × f value and density increase. In addition, the dielectric constant of BaZrO3 ceramics increases with the increase of Sr2+ addition. With excellent microwave dielectric properties, ϵ r = 34.17 and Q × f value of 39,070 GHz(@ 7.8 GHz) τf = + 140 ppm/°C were obtained in 6 at.-% Sr2+ doped BaZrO3 with 3 wt-% B2O3 sintering aid at 1275°C for 5 h. Using this material as the medium, the simulation of GPS antenna by HFSS software shows that this material has the potential to be used as the antenna medium material.
{"title":"Effect of Sr2+doping on the microwave dielectric properties of BaZrO3 ceramics","authors":"Dewei Cui, Hui Shao","doi":"10.1080/17436753.2023.2247682","DOIUrl":"https://doi.org/10.1080/17436753.2023.2247682","url":null,"abstract":"ABSTRACT In this study, undoped and Sr2+ doped BaZrO3 ceramics were prepared by solid-state reaction using 3 wt-% B2O3 as sintering aid. The phase composition and microstructure of BaZrO3 were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that introducing an appropriate amount of Sr2+ makes BaZrO3 ceramics Q × f value and density increase. In addition, the dielectric constant of BaZrO3 ceramics increases with the increase of Sr2+ addition. With excellent microwave dielectric properties, ϵ r = 34.17 and Q × f value of 39,070 GHz(@ 7.8 GHz) τf = + 140 ppm/°C were obtained in 6 at.-% Sr2+ doped BaZrO3 with 3 wt-% B2O3 sintering aid at 1275°C for 5 h. Using this material as the medium, the simulation of GPS antenna by HFSS software shows that this material has the potential to be used as the antenna medium material.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"6 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78915624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-23DOI: 10.1080/17436753.2023.2246000
F. D’Isanto, F. Smeacetto, M. Reece, M. Salvo
ABSTRACT Several oxidation protective coatings, both glass-based and ceramic/polymer hybrid coatings, for p- and n-type thermoelectrics were designed at the Politecnico di Torino in recent years, and they were characterised and tested under relevant conditions. The ‘glass-ceramic route’ to obtain a thermo-mechanical compatible and high-temperature resistant coated thermoelectric is discussed with some examples. Oxidation tests demonstrated the effectiveness of the coatings for the protection of both n- and p-type thermoelectrics.
{"title":"An overview of oxidation in hybrid and glass-based protective coatings for thermoelectric materials for medium-temperature range applications","authors":"F. D’Isanto, F. Smeacetto, M. Reece, M. Salvo","doi":"10.1080/17436753.2023.2246000","DOIUrl":"https://doi.org/10.1080/17436753.2023.2246000","url":null,"abstract":"ABSTRACT Several oxidation protective coatings, both glass-based and ceramic/polymer hybrid coatings, for p- and n-type thermoelectrics were designed at the Politecnico di Torino in recent years, and they were characterised and tested under relevant conditions. The ‘glass-ceramic route’ to obtain a thermo-mechanical compatible and high-temperature resistant coated thermoelectric is discussed with some examples. Oxidation tests demonstrated the effectiveness of the coatings for the protection of both n- and p-type thermoelectrics.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"42 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72484391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT High-entropy carbide (Ti0.2x Zr0.2x Hf0.2x + (1-x)Nb0.2x Ta0.2x )C x (HEC-(1-x)Hf, x = 0.6-1) ceramics with 0-40 at.% nominal carbon vacancy were prepared by adding metal Hf into (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C (HEC) as a case study. The samples prepared by spark plasma sintering at 2000oC exhibit relative densities higher than 99%, single-phase rock salt structure, and homogeneous metal elements distribution. Their lattice parameters increase gradually with the added Hf content. The lattice parameter of HEC-0.4Hf is 0.86% higher than HEC's. The average grain size of the samples decreased initially, followed by an increase as Hf content increased, which is controlled by the comprehensive effect of Hf addition and carbon vacancy. The thermal conductivities of the samples decrease with the increase of Hf addition. HEC-0.4Hf has a very low thermal conductivity of 5.6 W/m·K at room temperature, which decreases 67.8% compared to HEC. The increased phonon scattering by the carbon vacancies can be the main reason for the reduced thermal conductivity.
{"title":"From stoichiometric to non-stoichiometric high-entropy carbide: a case study of hafnium addition","authors":"Yuan Qin, Xiaofeng Wei, Ji‐Xuan Liu, Yongcheng Liang, Guo‐Jun Zhang","doi":"10.1080/17436753.2023.2243120","DOIUrl":"https://doi.org/10.1080/17436753.2023.2243120","url":null,"abstract":"ABSTRACT High-entropy carbide (Ti0.2x Zr0.2x Hf0.2x + (1-x)Nb0.2x Ta0.2x )C x (HEC-(1-x)Hf, x = 0.6-1) ceramics with 0-40 at.% nominal carbon vacancy were prepared by adding metal Hf into (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C (HEC) as a case study. The samples prepared by spark plasma sintering at 2000oC exhibit relative densities higher than 99%, single-phase rock salt structure, and homogeneous metal elements distribution. Their lattice parameters increase gradually with the added Hf content. The lattice parameter of HEC-0.4Hf is 0.86% higher than HEC's. The average grain size of the samples decreased initially, followed by an increase as Hf content increased, which is controlled by the comprehensive effect of Hf addition and carbon vacancy. The thermal conductivities of the samples decrease with the increase of Hf addition. HEC-0.4Hf has a very low thermal conductivity of 5.6 W/m·K at room temperature, which decreases 67.8% compared to HEC. The increased phonon scattering by the carbon vacancies can be the main reason for the reduced thermal conductivity.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"19 2 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78248154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT As a rare earth ortho-ferrite, NdFeO3 has strong magnetocrystalline anisotropy and can be used for microwave absorption, but its own wave absorption performance is poor. In this paper, Er3+ replaces Nd3+ to improve its microwave performance. Nd1−xErxFeO3 (0 ≤ x ≤ 0.15) was prepared by the sol -gel method. The hysteresis loops at 10 and 300 K are show that the saturation magnetisation increased with the doping content, its due to change of the magnetic moment direction and the magnetocrystalline anisotropy for the entry of Er. Meanwhile, this paper studied the ZFC-FC curve of 10 -300 K under 200 Oe and found that with the increase of doping content, the magnetic transition temperature gradually decreases. The entry of Er improves the dielectric properties of NdFeO3, there are a large number of oxygen vacancies and interface polarisation, which improves its absorption performance. When x = 0.15, the reflection loss reaches −39.21 dB and the bandwidth reaches 1.76 GHz, which can be applied to the Ku band microwave absorption field.
{"title":"Impact of Er substitution on the properties of NdFeO3: structural, magnetic and microwave absorption","authors":"Qihua Liang, Haotong Zhang, Zhaofei Tong, Jinxiang Guo, Man Wang, Q. Yao, Huai-ying Zhou","doi":"10.1080/17436753.2023.2243427","DOIUrl":"https://doi.org/10.1080/17436753.2023.2243427","url":null,"abstract":"ABSTRACT As a rare earth ortho-ferrite, NdFeO3 has strong magnetocrystalline anisotropy and can be used for microwave absorption, but its own wave absorption performance is poor. In this paper, Er3+ replaces Nd3+ to improve its microwave performance. Nd1−xErxFeO3 (0 ≤ x ≤ 0.15) was prepared by the sol -gel method. The hysteresis loops at 10 and 300 K are show that the saturation magnetisation increased with the doping content, its due to change of the magnetic moment direction and the magnetocrystalline anisotropy for the entry of Er. Meanwhile, this paper studied the ZFC-FC curve of 10 -300 K under 200 Oe and found that with the increase of doping content, the magnetic transition temperature gradually decreases. The entry of Er improves the dielectric properties of NdFeO3, there are a large number of oxygen vacancies and interface polarisation, which improves its absorption performance. When x = 0.15, the reflection loss reaches −39.21 dB and the bandwidth reaches 1.76 GHz, which can be applied to the Ku band microwave absorption field.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"1 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74055166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2238160
A. Naughton-Duszová, D. Medveď, Lenka Ďaková, A. Kovalčíková, P. Švec, P. Tatarko, Hakan Ünsal, P. Hvizdoš, P. Šajgalík, J. Dusza
ABSTRACT Wear characteristics of a fine-grained dual-phase high-entropy (Ti0.14Zr0.2Nb0.2Hf0.2Ta0.26)C + (Ti0.38Zr0.18Nb0.22Hf0.115Ta0.105)B2 were investigated using the ball-on-flat technique/dry sliding in air. The experimental material showed very high density with a value of 8.72 g/cm3 and a small grain size of HEC and HEB grains with values of 0.95 ± 0.30 and 0.99 ± 0.27 μm, respectively. The nano-hardness of the HEC and HEB grains is very high with mean values of 37.4 ± 2.3 and 43.0 ± 2.9 GPa, respectively with the micro-hardness of the dual system HV1 29.4 ± 2.0 GPa. The friction coefficient values during the test with 5 and 10 N increased from a value of 0.4 and reached the values 0.65 and 0.77 at the sliding distances of approximately 1500 and 1000 m, respectively. The specific wear rate decreased with increasing sliding distance at 5 N load, from 4.75 × 10−7 mm3/Nm to 4.2 × 10−7 mm3/Nm and at 10 N from 2.1 × 10−7 to 1.7 × 10−7 mm3/Nm. The dominant wear mechanisms in both cases were an oxidation-driven tribo-chemical reaction and tribo-layer formation in boride grains and mechanical wear in carbide grains.
{"title":"Highly wear resistant dual-phase (Ti-Zr-Nb-Hf-Ta)C/(Ti-Zr-Nb-Hf-Ta) B2 high-entropy ceramics","authors":"A. Naughton-Duszová, D. Medveď, Lenka Ďaková, A. Kovalčíková, P. Švec, P. Tatarko, Hakan Ünsal, P. Hvizdoš, P. Šajgalík, J. Dusza","doi":"10.1080/17436753.2023.2238160","DOIUrl":"https://doi.org/10.1080/17436753.2023.2238160","url":null,"abstract":"ABSTRACT Wear characteristics of a fine-grained dual-phase high-entropy (Ti0.14Zr0.2Nb0.2Hf0.2Ta0.26)C + (Ti0.38Zr0.18Nb0.22Hf0.115Ta0.105)B2 were investigated using the ball-on-flat technique/dry sliding in air. The experimental material showed very high density with a value of 8.72 g/cm3 and a small grain size of HEC and HEB grains with values of 0.95 ± 0.30 and 0.99 ± 0.27 μm, respectively. The nano-hardness of the HEC and HEB grains is very high with mean values of 37.4 ± 2.3 and 43.0 ± 2.9 GPa, respectively with the micro-hardness of the dual system HV1 29.4 ± 2.0 GPa. The friction coefficient values during the test with 5 and 10 N increased from a value of 0.4 and reached the values 0.65 and 0.77 at the sliding distances of approximately 1500 and 1000 m, respectively. The specific wear rate decreased with increasing sliding distance at 5 N load, from 4.75 × 10−7 mm3/Nm to 4.2 × 10−7 mm3/Nm and at 10 N from 2.1 × 10−7 to 1.7 × 10−7 mm3/Nm. The dominant wear mechanisms in both cases were an oxidation-driven tribo-chemical reaction and tribo-layer formation in boride grains and mechanical wear in carbide grains.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"24 1","pages":"107 - 118"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84860557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2227446
W. Jibran, P. Wanjara, Javad Gholipour Baradari, Maria Ophelia Jarligo, A. McDonald
ABSTRACT This study presents a novel approach for surface repairs of high-strength, cold-worked aluminium (Al) alloys, without negatively affecting the base material strength. Low-pressure cold spraying was used to fabricate Al–Al2O3 metal matrix composite overlays, with varying concentrations of Al2O3 deposited on an Al alloy. Friction stir processing (FSP) was employed to disperse and consolidate the overlay coating on the base material. The FSP was found to improve the Al2O3 particle distribution in the coating and reduce the mean free path between Al2O3 particles. The coating hardness increased after FSP. The post-FSPed overlays also exhibited lower wear rates compared to the as-sprayed condition. Remarkable improvement was observed in the tensile properties of the coatings, which were attributed to the improved dispersion of Al2O3 particles in the matrix, while the enhanced ductility was attributed to the possible grain refinement that occurred due to the recrystallisation of Al during FSP.
{"title":"Localised surface modification of high-strength aluminium–alumina metal matrix composite coatings using cold spraying and friction stir processing","authors":"W. Jibran, P. Wanjara, Javad Gholipour Baradari, Maria Ophelia Jarligo, A. McDonald","doi":"10.1080/17436753.2023.2227446","DOIUrl":"https://doi.org/10.1080/17436753.2023.2227446","url":null,"abstract":"ABSTRACT This study presents a novel approach for surface repairs of high-strength, cold-worked aluminium (Al) alloys, without negatively affecting the base material strength. Low-pressure cold spraying was used to fabricate Al–Al2O3 metal matrix composite overlays, with varying concentrations of Al2O3 deposited on an Al alloy. Friction stir processing (FSP) was employed to disperse and consolidate the overlay coating on the base material. The FSP was found to improve the Al2O3 particle distribution in the coating and reduce the mean free path between Al2O3 particles. The coating hardness increased after FSP. The post-FSPed overlays also exhibited lower wear rates compared to the as-sprayed condition. Remarkable improvement was observed in the tensile properties of the coatings, which were attributed to the improved dispersion of Al2O3 particles in the matrix, while the enhanced ductility was attributed to the possible grain refinement that occurred due to the recrystallisation of Al during FSP.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"21 1","pages":"181 - 196"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81207703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2231699
E. Medvedovski, Gerardo Leal Mendoza
ABSTRACT Vitreous ceramic-like enamel coatings can be applied onto low-alloy and carbon steel components of various configurations, including tubulars, by different cost-effective technological methods achieving thicknesses up to 300 µm. Corrosion resistance of the enamel coatings in acidic environments, boiling brines and high temperature – high pressure (HT-HP) steam with a presence of CO2-H2S containing gases simulating some processes in refinery, oil & gas and geothermal production was tested and evaluated. Specifically, the testing in simulating HT-HP downhole production conditions was conducted for the enamel coatings for the first time. Microstructural examination and analysis of the obtained enamel glassy coatings revealed their insignificant compositional and structural degradation. A high level of steel protection by enamelling in considered environments demonstrated these coatings’ potential for different corrosion-related industrial processes.
{"title":"Enamel (glassy) coatings for steel protection against high temperature corrosion","authors":"E. Medvedovski, Gerardo Leal Mendoza","doi":"10.1080/17436753.2023.2231699","DOIUrl":"https://doi.org/10.1080/17436753.2023.2231699","url":null,"abstract":"ABSTRACT Vitreous ceramic-like enamel coatings can be applied onto low-alloy and carbon steel components of various configurations, including tubulars, by different cost-effective technological methods achieving thicknesses up to 300 µm. Corrosion resistance of the enamel coatings in acidic environments, boiling brines and high temperature – high pressure (HT-HP) steam with a presence of CO2-H2S containing gases simulating some processes in refinery, oil & gas and geothermal production was tested and evaluated. Specifically, the testing in simulating HT-HP downhole production conditions was conducted for the enamel coatings for the first time. Microstructural examination and analysis of the obtained enamel glassy coatings revealed their insignificant compositional and structural degradation. A high level of steel protection by enamelling in considered environments demonstrated these coatings’ potential for different corrosion-related industrial processes.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"52 1","pages":"145 - 169"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88323007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2231230
P. Mechnich, G. Alkan
ABSTRACT The solid particle technology usage in concentrated solar power plants as direct heat absorption and storage medium necessitate well selection of the materials for the components such as transport and sluice systems, which are in direct contact with moving and falling hot particles up to 1500 ˚C. Beyond mechanical properties, chemical inertness and high-temperature stability, abrasion/erosion resistance are one of the key properties, for which, there is no easy-applicable and rapid test method exist enabling controlled lab-scale parametric studies. A novel particle impact test was established using a resonance acoustic mixer, in which ceramic particles are strongly accelerated and collide with the ceramic surface within a closed vessel. After determination of the most representative parameters such as ceramic ball size, vessel diameter, and retainment/removal of debris, selected experiments were conducted on three candidate materials aimed to be used as high-temperature transport/port systems; dense C 799 Al2O3, porous water-plasma sprayed Plascera-type Al2O3 and WHIPOX-type Al2O3/Al2O3 ceramic matrix composites with porous matrix; with and without porous protective Al2O3 coating. The distinct mass loss behaviour of candidate materials highlighted the viability of the test method and the relevance of microstructures of porous Al2O3 materials on abrasion resistance.
{"title":"Rapid evaluation of the particle-erosion resistance of Al2O3 ceramics, composites, and coatings using a resonant acoustic mixer","authors":"P. Mechnich, G. Alkan","doi":"10.1080/17436753.2023.2231230","DOIUrl":"https://doi.org/10.1080/17436753.2023.2231230","url":null,"abstract":"ABSTRACT The solid particle technology usage in concentrated solar power plants as direct heat absorption and storage medium necessitate well selection of the materials for the components such as transport and sluice systems, which are in direct contact with moving and falling hot particles up to 1500 ˚C. Beyond mechanical properties, chemical inertness and high-temperature stability, abrasion/erosion resistance are one of the key properties, for which, there is no easy-applicable and rapid test method exist enabling controlled lab-scale parametric studies. A novel particle impact test was established using a resonance acoustic mixer, in which ceramic particles are strongly accelerated and collide with the ceramic surface within a closed vessel. After determination of the most representative parameters such as ceramic ball size, vessel diameter, and retainment/removal of debris, selected experiments were conducted on three candidate materials aimed to be used as high-temperature transport/port systems; dense C 799 Al2O3, porous water-plasma sprayed Plascera-type Al2O3 and WHIPOX-type Al2O3/Al2O3 ceramic matrix composites with porous matrix; with and without porous protective Al2O3 coating. The distinct mass loss behaviour of candidate materials highlighted the viability of the test method and the relevance of microstructures of porous Al2O3 materials on abrasion resistance.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"47 1","pages":"250 - 257"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80485008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2230675
L. Ćurković, Ivana Ropuš, Ivan Gabelica, Sanda Rončević
ABSTRACT The most widely used ceramic material is aluminium oxide, known as alumina. Due to its superior properties such as chemical stability, high wear resistance, refractoriness and so on, it is ideal for applications in aggressive environment. This type of environment often includes exposure to corrosive solids, liquids and gases. When ceramics come in contact with corrosive medium, several corrosion mechanisms can occur, depending on a number of parameters. Therefore, the corrosion behaviour of cold isostatically pressed (CIP) high purity alumina ceramics was observed under different conditions: 0.5, 1.25 and 2 mol dm−3 of nitric acid at 25°C, 40°C and 55°C through 10 days. Purity of used alumina ceramics was 99.8345 wt. % with 0.1655 wt. % of both sintering aid (MgO) and impurities (SiO2, CaO, Na2O and Fe2O3). The results show that Al2O3 ceramics exhibit good corrosion resistance in nitric acid. Al2O3 corrosion behaviour varies depending on the temperature, time and HNO3 concentration. In view of the reaction kinetics, it proceeds in the near-parabolic law in HNO3 aqueous solution and decreases with an increase of the HNO3 concentration.
{"title":"Kinetics investigation of alumina ceramics corrosion in nitric acid","authors":"L. Ćurković, Ivana Ropuš, Ivan Gabelica, Sanda Rončević","doi":"10.1080/17436753.2023.2230675","DOIUrl":"https://doi.org/10.1080/17436753.2023.2230675","url":null,"abstract":"ABSTRACT The most widely used ceramic material is aluminium oxide, known as alumina. Due to its superior properties such as chemical stability, high wear resistance, refractoriness and so on, it is ideal for applications in aggressive environment. This type of environment often includes exposure to corrosive solids, liquids and gases. When ceramics come in contact with corrosive medium, several corrosion mechanisms can occur, depending on a number of parameters. Therefore, the corrosion behaviour of cold isostatically pressed (CIP) high purity alumina ceramics was observed under different conditions: 0.5, 1.25 and 2 mol dm−3 of nitric acid at 25°C, 40°C and 55°C through 10 days. Purity of used alumina ceramics was 99.8345 wt. % with 0.1655 wt. % of both sintering aid (MgO) and impurities (SiO2, CaO, Na2O and Fe2O3). The results show that Al2O3 ceramics exhibit good corrosion resistance in nitric acid. Al2O3 corrosion behaviour varies depending on the temperature, time and HNO3 concentration. In view of the reaction kinetics, it proceeds in the near-parabolic law in HNO3 aqueous solution and decreases with an increase of the HNO3 concentration.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"36 1","pages":"129 - 136"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84033877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/17436753.2023.2236888
G. Fisher, D. Diaz
ABSTRACT The Albertan oil sands surface mining industry recovers and processes large quantities of ore to remove the bitumen from the oil sands. The scale of the operations and the abrasive nature of the ore results in very aggressive wear conditions. The high levels of abrasive and impact wear can lead to equipment reliability issues, with associated costs and lost production. As such, it is common to augment the durability of mining components by the application of wear-resistant materials. For critical equipment tungsten carbide-based composite overlays are commonly selected to improve reliability and extend service life. The performance of the overlay is very much dependent on the service conditions. This paper will describe how the selection of tungsten carbide-type can determine the performance of a composite overlay in a range of abrasive and impact wear conditions. The paper will demonstrate how the effective selection of the composite to match the expected service conditions can improve the durability of mining equipment.
{"title":"The design and selection of tungsten carbide-based composite overlays for aggressive wear service conditions","authors":"G. Fisher, D. Diaz","doi":"10.1080/17436753.2023.2236888","DOIUrl":"https://doi.org/10.1080/17436753.2023.2236888","url":null,"abstract":"ABSTRACT The Albertan oil sands surface mining industry recovers and processes large quantities of ore to remove the bitumen from the oil sands. The scale of the operations and the abrasive nature of the ore results in very aggressive wear conditions. The high levels of abrasive and impact wear can lead to equipment reliability issues, with associated costs and lost production. As such, it is common to augment the durability of mining components by the application of wear-resistant materials. For critical equipment tungsten carbide-based composite overlays are commonly selected to improve reliability and extend service life. The performance of the overlay is very much dependent on the service conditions. This paper will describe how the selection of tungsten carbide-type can determine the performance of a composite overlay in a range of abrasive and impact wear conditions. The paper will demonstrate how the effective selection of the composite to match the expected service conditions can improve the durability of mining equipment.","PeriodicalId":7224,"journal":{"name":"Advances in Applied Ceramics","volume":"25 1","pages":"170 - 180"},"PeriodicalIF":2.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83019915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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