Physico-mechanical properties and microstructure of multi-phase ceramic composites based on zircon and dolomite mixtures

2021 ◽  
Vol 19 (4) ◽  
pp. 305-314
Author(s):  
M.M.S. Wahsh ◽  
Safyah B. Bakare ◽  
I.M. Bakr ◽  
A.G.M. Othman
Keyword(s):  
Mechanical Properties ◽  
Bulk Density ◽  
Tetragonal Zirconia ◽  
Porous Ceramics ◽  
Ceramic Composites ◽  
Liquid Phase Sintering ◽  
Apparent Porosity ◽  
Transformation Toughening ◽  
Linear Change ◽  
Multi Phase

Four composites containing zircon and dolomite were designed by adding dolomite from 5wt% to 35wt% at the expense of zircon content. Densification parameters in terms of bulk density, apparent porosity and linear change were determined at different firing temperatures (1200°C–1400°C). Cold crushing strength of sintered composites, phase composition and microstructure were investigated. Samples contain 35wt% of dolomite and fired at 1200°C for 2 hours exhibited higher porosity (AP ∼ 51.25%) than other samples and can be used as porous ceramics. This is due to CO2 evaporation through the thermal decomposition of dolomite. Dense ceramics can be obtained by adding 5wt% of dolomite and fired at 1400°C for 2 hours (bulk density ∼3.67 g/cm3 and apparent porosity ∼4.5%). Only zirconia and diopside crystalline phases were detected at composite containing 35wt% of dolomite and fired at 1400°C. Due to the liquid phase sintering process, the densification parameters of the sintered samples have been enhanced by increasing the temperature. The mechanical properties of the sintered samples were improved due to the transformation toughening mechanism of tetragonal zirconia. Microstructure and EDAX analysis of the sintered composites show the presence of sub-prismatic zircon and rounded zirconia crystals as well as irregularly dark diopside crystals.

Mechanical Properties and Thermal Conductivity of Lightweight Clay Bricks Fabricated with a Powdered Marble Dust Additive

2018 ◽  
Vol 777 ◽  
pp. 465-470
Author(s):  
Sutas Janbuala ◽  
Mana Eambua ◽  
Arpapan Satayavibul ◽  
Watcharakhon Nethan
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Compressive Strength ◽  
Water Absorption ◽  
Bulk Density ◽  
Firing Temperature ◽  
Apparent Porosity ◽  
Clay Brick ◽  
Clay Bricks ◽  
Marble Dust

The objective of this study was to recycle powdered marble dust to improve mechanical properties and thermal conductivity of lightweight clay bricks. Varying amounts of powdered marble dust (10, 20, 30, and 40 vol.%) were added to a lightweight clay brick at the firing temperatures of 900, 1000, and 1100 °C. When higher quantities of powdered marble dust were added, the values of porosity and water absorption increased while those of thermal conductivity and bulk density decreased. The decrease in apparent porosity and water absorption were also affected by the increase in firing temperature. The most desirable properties of the clay bricks were obtained for the powdered marble dust content of 40 vol.% and firing temperature 900 °C: bulk density of 1.20 g/cm3, compressive strength 9.2 MPa, thermal conductivity 0.32 W/m.K, and water absorption 22.5%.

The Influences of Addition of MgCO3 on the Properties of the Magnesia Prepared Using Magnesite

2018 ◽  
Vol 281 ◽  
pp. 230-235
Author(s):  
Wang Nian Zhang ◽  
Li Wang ◽  
Ni Deng
Keyword(s):  
Grain Size ◽  
Bulk Density ◽  
Raw Materials ◽  
Apparent Porosity ◽  
X Ray Diffraction ◽  
Linear Change ◽  
Change Rate ◽  
X Ray ◽  
Before And After ◽  
Calcination Method

Micropowder MgCO3 was added into magnesite as raw materials to prepare magnesia using a two-step calcination method. The sample magnesite was characterized use X-ray diffraction (XRD) and scanning electron microscopy (SEM). Experimental results showed that the sample insulated at 1600° C for 3 hours before and after sintering presented a linear change rate of 15.6 % in the case of without adding micropowder MgCO3, the prepared magnesia had a bulk density of 2.31 g/cm3 and apparent porosity of 32.8 %, while MgO grain size was 3.11 μm. In the case of adding 8 % micropowder MgCO3, the sample magnesite before and after sintering showed a linear change rate of 17.9 %. The bulk density, apparent porosity of prepared magnesia were 2.46 g/cm3 and 28.1 % respectively, while the grain size of MgO was 5.15 mm.

scholarly journals Si3N4-SiCpComposites Reinforced byIn SituCo-Catalyzed Generated Si3N4Nanofibers

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Juntong Huang ◽  
Zhaohui Huang ◽  
Shaowei Zhang ◽  
Minghao Fang ◽  
Yan’gai Liu
Keyword(s):  
Mechanical Properties ◽  
Bulk Density ◽  
Bending Strength ◽  
Sintering Temperature ◽  
Apparent Porosity ◽  
Network Connection ◽  
Opposite Trend ◽  
Low Sintering Temperature ◽  
Co Addition

Si3N4-SiCpcomposites reinforced byin situcatalytic formed nanofibers were prepared at a relatively low sintering temperature. The effects of catalyst Co on the phase compositions, microstructures, and physicochemical-mechanical properties of samples sintered at 1350°C–1450°C were investigated. The results showed that the catalyst Co enhanced the nitridation of Si. With the increase of Co addition (from 0 wt% to 2.0 wt.%), the apparent porosity of as-prepared refractories was initially decreased and subsequently increased, while the bulk density and the bending strength exhibited an opposite trend. TheSi3N4-SiCpcomposites sintered at 1400°C had the highest strength of 60.2 MPa when the Co content was 0.5 wt.%. The catalyst Co facilitated the sintering ofSi3N4-SiCpcomposites as well as the formation of Si3N4nanofibers which exhibited network connection and could improve their strength.

scholarly journals Microstructure Characteristics of Ce-ZTA Ceramic Composites Obtained by Liquid Phase Sintering

2006 ◽  
Vol 530-531 ◽  
pp. 421-424
Author(s):  
Haine Beck ◽  
Maria do Carmo de Andrade Nono ◽  
Francisco Piorino Neto
Keyword(s):  
Ceramic Composite ◽  
Glassy Phase ◽  
Volume Fraction ◽  
Tetragonal Zirconia ◽  
Ceramic Composites ◽  
Liquid Phase Sintering ◽  
Scanning Electronic Microscopy ◽  
Powder Samples ◽  
Zirconia Toughened Alumina ◽  
Crystalline Matrix

Zirconia-toughened alumina (ZTA) ceramics with Ce-TZP (tetragonal zirconia polycrystalline doped with ceria) volume fraction on 33% were prepared with the addition.. The influence of glass infiltrated method was investigated. Coprecipitated Zr and Ce hydroxide mixture was obtained from ZrOCl2.8H2O and CeCl3. 7H2O aqueous solution. CeO2-ZrO2 calcinated powder was compacted and the compacted samples were sintered at 1180°C. Powder samples were characterized by scanning electronic microscopy (SEM), The volume fraction of each phase, the grains size and shapes, and the porosity were investigated with SEM. The relative density and shrinkage was investigate too. The results showed that the crystalline matrix was composed by SiO2 -B2O3-La2O3-Al2O3-Ce-TZP and revealed the important role played the glassy phase in the densification of this ceramic composite.

scholarly journals Effect of firing temperature on physico-mechanical properties of contemporary clay brick productions in Lalitpur, Nepal

2020 ◽  
Vol 55 (1) ◽  
pp. 43-52 ◽  
Author(s):  
NB Bohara ◽  
DB Ghale ◽  
YP Chapagain ◽  
N Duwal ◽  
J Bhattarai
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Physical Properties ◽  
Bulk Density ◽  
Firing Temperature ◽  
Apparent Porosity ◽  
Clay Brick ◽  
Mechanical And Physical Properties ◽  
Fired Bricks ◽  
Maximum Compressive Strength

Effect of firing temperature on some physico-mechanical properties of ten brick samples, those were composed by feldspars, quartz, alumina-rich spinel, primary mullite and hematite phases, was investigated in accordance with ASTM standards. The brick samples fired between 700° to 1100° C showed 11-23 % water adsorptivity (WA), 19-37 % apparent porosity (AP) and 1.50-1.65 g/cm3 bulk density (BD) indicate good physical properties. The maximum compressive strength (CS) of the fired-bricks at 950° to 1000° C was found to be between 15.6 and 17.1 MPa. At 700°-1000° C firing temperatures, the CS of these bricks is found to be increased exponentially with decreasing of both WA and AP, however it is found to be increased with increasing the BD. Consequently, it can be said that there is good correlation between mechanical and physical properties of the fired-brick samples up to the firing temperature of 1000° C. Bangladesh J. Sci. Ind. Res.55(1), 43-52, 2020

Influence of Sintering Temperature on Physical and Mechanical Properties of Hydroxyapatite-Calcium Titanate Composite

2019 ◽  
Vol 805 ◽  
pp. 65-70
Author(s):  
Suchittra Inthong ◽  
Denis Russell Sweatman ◽  
Sukum Eitssayeam ◽  
Tawee Tunkasiri
Keyword(s):  
Mechanical Properties ◽  
Physical Properties ◽  
Bulk Density ◽  
Vickers Microhardness ◽  
Sintering Temperature ◽  
Physical And Mechanical Properties ◽  
Calcium Titanate ◽  
Apparent Porosity

This research is concerned with the effect of sintering temperature on physical and mechanical properties. This Hydroxyapatite-calcium titanate (HA-CT) composites were synthesized using conventional route technique. The HA-CT composites were sintered between 1200 up to 1300 °C. The effect of sintering temperature on the physical and mechanical properties of HA-CT composites was discussed. The physical properties were studied in term of densification and apparent porosity. As well as, the mechanical properties were determined in term of Vickers microhardness. The increasing of the sintering temperature increased both of the bulk density and the Vickers microhardness properties. However, the apparent porosity was decreased with increasing sintering temperature. The highest bulk density was found at 0.15 mol.% of CT in HA-CT composites which was sintered at 1300 °C for 3 h. Moreover, the mechanical properties as a function of the sintering temperature and the CT contents were also discussed and compared with other related work.

scholarly journals Physical and Mechanical Properties of a Porous Material Obtained by Low Replacement of Volcanic Ash by Aluminum Beverage Cans

2021 ◽  
pp. 1-11
Author(s):  
Bernard Missota Priso Dickson ◽  
Claudine Mawe Noussi ◽  
Louise Ndongo Ebongue ◽  
Joseph Dika Manga
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Porous Material ◽  
Water Absorption ◽  
Bulk Density ◽  
Volcanic Ash ◽  
Physical And Mechanical Properties ◽  
Apparent Porosity ◽  
Partial Replacement ◽  
Inorganic Polymers

This study focuses on the evaluation of the physical and mechanical properties of a porous material based on a mixture of powder (Volcanic ash /Aluminum Beverage Cans) and a solution of phosphoric acid. Volcanic ash (VA) use was collected in one of the quarries of Mandjo (Cameroon coastal region), crushed, then characterized by XRF, DRX, FTIR and named MaJ. The various polymers obtained are called MaJ0, MaJ2.5, MaJ5, MaJ7.5 and MaJ10 according to the mass content of the additions of the powder from the aluminum beverage cans (ABCs). The physical and mechanical properties of the synthetic products were evaluated by determining the apparent porosity, bulk density, water absorption and compressive strength. The results of this study show that the partial replacement of the powder of VA by that of ABC leads to a reduction in the compressive strength (5.9 - 0.8 MPa) and bulk density (2.56 – 1.32 g/cm3) of the polymers obtained. On the other hand, apparent porosity, water absorption and pore formation within the polymers increases with addition of the powder from the beverage cans. All of these results allow us to agree that the ABCs powder can be used as a blowing agent during the synthesis of phosphate inorganic polymers.

scholarly journals Evaluation of Chemical and Physico-Mechanical Properties of some Nigeria Natural Clays Samples for Foundry Applications

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Yusuf L Shuaib-Babata ◽  
Abdulhafeez N Abdulrahaman
Keyword(s):  
Mechanical Properties ◽  
Bulk Density ◽  
Economic Recession ◽  
Linear Shrinkage ◽  
Apparent Porosity ◽  
Economic Activities ◽  
Medium Temperature ◽  
Iron And Steel ◽  
Brick Lining ◽  
Alumino Silicate

Studies have shown that Nigerian clays have not been fully utilized for foundry applications, either as refractories or even bonding clays, and are still being imported into the country. There is need to effectively exploit and adequately utilize the available natural resources to improve Nigeria economic activities, most especially during the present economic recession. Samples of clays were obtained from Auchi, Dada-Okelele (Ilorin), Kaba, Maraba-Rido, Mokwa and New-Bussa in Nigeria. The samples’ physico-mechanical properties were examined for its suitability for foundry/refractory applications. The results of the chemical analysis revealed that the samples belong to Alumino-Silicate refractories. The samples exhibited 35.3-96.2%, 17.1-28.7%, 1.72-2.34 g/cm3, 2.2-10.1%, 73-86 and >1300oC as values for percentage clay contents, apparent porosity, bulk density, permeability, linear shrinkage and refractoriness respectively. These values were within the standard range values of >35%, 22-30%, 17-2.4%, 2.0-10.1% and 25-90 required as percentage clay contents, apparent porosity, bulk density, permeability and linear shrinkage values respectively, for refractory clays/brick lining or alumina-silicates, kaolin and fireclays. Hence, the clays could suitably replace imported clays / ceramics in refractory applications, such as in production of earthen wares, chalk; as insulating refractories for casting and melting of low and medium temperature iron and steel. Appropriate utilization of these clays for local foundry applications will assist in addressing the problem of inadequate job, and over dependence on foreign goods.Keywords— Alumino-Silicate, Clay, Foundry, Moisture and Refractoriness

Sintering Characters Analysis of the Al2O3-86 Homogenized Bauxite

2013 ◽  
Vol 690-693 ◽  
pp. 35-39
Author(s):  
Huan Ying Yang ◽  
Yong Li ◽  
Shu Long Liu ◽  
Chang He Gao ◽  
Shu Long Ma ◽  
...  
Keyword(s):  
Weight Loss ◽  
Liquid Phase ◽  
Bulk Density ◽  
Tunnel Kiln ◽  
Liquid Phase Sintering ◽  
Sintering Process ◽  
Linear Change ◽  
Phase Form ◽  
Different Temperatures ◽  
Positive Effect

The present explains sintering characters of the Al2O3-86 homogenized bauxite under wet processes homogenization, which includes classified bauxite mine, wet grinding, vacuum extrusion, sintering in tunnel kiln,etc. DSC and TG reveal an evident peak of absorption heat at 531°C, resulting from the dehydroxylation of bauxite. Green samples held at 550°C*6hrs were heated up to different temperatures, and the properties of weight loss, linear change, bulk density and apparent porosity were measured. The data show that liquid-phase emerge and sintering process goes slowly above 1100°C. At 1500°C, large amounts of liquid-phase form, making liquid-phase sintering have a positive effect. The analysis of XRD and SEM indicate that, corundum grains develop more inadequate and most of the corundums interlace in a compact way, which can separate the widespread liquid phase and improve the sintering capability of homogenized bauxite.

Effect of Z Values on the Microstructure and Mechanical Properties of Post-sintered Reaction Bonded β-SiAlON

2017 ◽  
Vol 36 (5) ◽  
pp. 453-458 ◽  
Author(s):  
Yanjun Li ◽  
Donghua Liu ◽  
Han Jin ◽  
Donghai Ding ◽  
Guoqing Xiao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Phase Composition ◽  
Bulk Density ◽  
Grain Growth ◽  
Bending Strength ◽  
Raw Materials ◽  
Apparent Porosity ◽  
Reaction Bonding ◽  
Microstructure And Mechanical Properties ◽  
Before And After

Abstractβ-SiAlON materials with different Z values (Z=0.5–3) were fabricated by a reaction bonding combining post-sintering route using raw materials of Si, Al2O3, AlN, etc. The reaction bonded β-SiAlON (RB-β-SiAlON) were post-sintered at 1,750 °C for 6 h. Apparent porosity, bulk density, bending strength and Vicker’s hardness of the samples before and after post-sintering were tested. XRD results showed that the phase composition of both RB-β-SiAlON and post-sintered RB-β-SiAlON (PSRB-β-SiAlON) were β-SiAlON. For RB-β-SiAlON, the apparent porosity was decreased with the increase of Z values, while the strength and hardness was increased accordingly. After the post-sintering procedure, nearly full densified PSRB-β-SiAlON was obtained and the mechanical properties were significantly improved. The bending strength and Vicker’s hardness of the PSRB-β-SiAlON (Z=0.5) achieved 510 MPa and 16.5 GPa, respectively, which were as 2.7 and 6.7 times high as those of the corresponding RB-β-SiAlON. However, the strength and hardness of PSRB-β-SiAlON decreased with the increase of Z value due to the grain growth.

Sign in / Sign up

Export Citation Format

Share Document