scholarly journals Effect of Thermal Shock on Bending Strength of Composites Made from Fly Ash and Glass Waste

2011 ◽  
Vol 8 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Jamasri, Muhammad Waziz Wildan ◽  
Kusnanto. Kusnanto
Keyword(s):  
Fly Ash ◽  
Thermal Shock ◽  
Bending Strength ◽  
Raw Materials ◽  
Weight Fraction ◽  
Bending Test ◽  
Experimental Result ◽  
Thermal Shock Test ◽  
Green Body ◽  
Glass Waste

The bending strength of composite made from fly ash and glass waste can be improved by controlling chemical composition of the raw materials and sintering temperatures. In this study, the composites made from mixture of various weight fractions between fly ash (FA) and glass waste (GL). Each mixture was uni-axially pressed with various compacting pressures to produce green body. The formed green body was then sintered at various temperatures from 900 °C to 1100°C for 2h. From the experimental result, it shows that the bending strength of composite fly ash and glass waste is highly varied based on the weight fraction of glass waste content, sintering temperatures and compacting pressures. The highest bending strength value is 44.53 MPa obtained from specimen that contains 50 (% wt.) of glass waste with sintering temperature of 1050 °C and compacting pressure of 130 MPa. A thermal shock test was performed on the specimen composites of 50FA-50GL by heating up to various temperatures and followed by quenching (rapid cooling) to water media. Bending test was then done on the thermal shocked specimen. The bending strength of specimen decreases sharply around 80.93 % from its original strength when subjected to temperature gradient (ΔT) of 285 °C.

Monitoring of Chemical Resistance of New Grouting Materials

2021 ◽  
Vol 898 ◽  
pp. 27-33
Author(s):  
Petr Figala ◽  
Rostislav Drochytka ◽  
Vit Černý ◽  
Radek Hermann ◽  
Jiří Kolísko
Keyword(s):  
Fly Ash ◽  
Chemical Resistance ◽  
Raw Materials ◽  
Waste Glass ◽  
Sulphate Solution ◽  
Sulphate Attack ◽  
Glass Waste ◽  
Foundry Sand ◽  
Waste Foundry Sand ◽  
Grouting Materials

This paper deals with the study of chemical resistance of new cement-based grout for invert grouting. The aim of this work is to verify new mixtures with specific admixtures. The study monitors resistance to external sulphate attack. Specimens were placed into sulphate solution 29.8 g∙l-1 (44 g∙l-1 Na2SO4) according to DIN19753 standard. Based on the results gained, new mixtures will be designed and optimized by addition of suitable secondary raw materials (fly ash, waste foundry sand, waste glass, waste filers).

scholarly journals Effective reinforcements for thermoplastics based on carbon nanotubes of oil fly ash

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Numan Salah ◽  
Abdulrahman Muhammad Alfawzan ◽  
Abdu Saeed ◽  
Ahmed Alshahrie ◽  
Waleed Allafi
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Fly Ash ◽  
Young’S Modulus ◽  
Raw Materials ◽  
Young's Modulus ◽  
Weight Fraction ◽  
Low Weight ◽  
Oil Fly Ash

AbstractCarbon nanotubes (CNTs) are widely investigated for preparing polymer nanocomposites, owing to their unique mechanical properties. However, dispersing CNTs uniformly in a polymer matrix and controlling their entanglement/agglomeration are still big technical challenges to be overcome. The costs of their raw materials and production are also still high. In this work, we propose the use of CNTs grown on oil fly ash to solve these issues. The CNTs of oil fly ash were evaluated as reinforcing materials for some common thermoplastics. High-density polyethylene (HDPE) was mainly reinforced with various weight fractions of CNTs. Xylene was used as a solvent to dissolve HDPE and to uniformly disperse the CNTs. Significantly enhanced mechanical properties of HDPE reinforced at a low weight fraction of these CNTs (1–2 wt.%), mainly the tensile strength, Young’s modulus, stiffness, and hardness, were observed. The tensile strength and Young’s modulus were enhanced by ~20 and 38%, respectively. Moreover, the nanoindentation results were found to be in support to these findings. Polycarbonate, polypropylene, and polystyrene were also preliminarily evaluated after reinforcement with 1 wt.% CNTs. The tensile strength and Young’s Modulus were increased after reinforcement with CNTs. These results demonstrate that the CNTs of the solid waste, oil fly ash, might serve as an appropriate reinforcing material for different thermoplastics polymers.

Properties of Low-Carbon Al2O3-C Refractories with Different Critical Particle Size

2012 ◽  
Vol 217-219 ◽  
pp. 318-321
Author(s):  
Chong Chong Niu ◽  
Guo Qi Liu ◽  
Xiao Xian Wu ◽  
Jian Bin Yu ◽  
Hong Bin Qin
Keyword(s):  
Particle Size ◽  
Fracture Energy ◽  
Thermal Shock ◽  
Raw Materials ◽  
Modulus Of Rupture ◽  
Thermal Shock Test ◽  
Low Carbon ◽  
Shock Resistance ◽  
Critical Particle Size ◽  
Α Al2o3

Low-carbon Al2O3-C refractories were prepared using white fused corundum, α-Al2O3 powders and flake graphite as main raw materials. The critical particle sizes of corundum selected in this experiment were 0.5mm, 1mm and 2mm. The effects of corundum critical particle size on physical, mechanical and thermo-mechanical properties of low-carbon Al2O3-C refractories were investigated. The results show that the increase of critical particle size is conducive to the improvement of thermal shock resistance and fracture energy, but little effect on thermal expansion. The cold modulus of rupture after thermal shock test of samples using 0.5mm critical particle size corundum was 2.09MPa, while using 2mm critical particle size corundum was 2.98MPa. And the fracture energy increased from 265N/mm to 588N/mm when the critical particle size increased from 0.5mm to 2mm. The effects of critical particle size on apparent porosity, bulk density and modulus of rupture were insignificant.

Thermal and Thermomechanical Properties of Refractory Forsterite-Spinel Ceramics

2021 ◽  
Vol 325 ◽  
pp. 174-180
Author(s):  
Martin Nguyen ◽  
Radomír Sokolář
Keyword(s):  
Fly Ash ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Raw Materials ◽  
Thermal Analyses ◽  
Aluminium Oxide ◽  
Thermomechanical Properties ◽  
Modulus Of Rupture ◽  
Shock Resistance

This article examines the utilization of fly ash in comparison with alumina as raw materials and sources of aluminium oxide for synthesis of forsterite-spinel refractory ceramics. Raw materials were milled, mixed in different ratios into two sets of mixtures and sintered at 1500°C for 2 hours. Sintered samples were characterized by X-ray diffraction analysis and scanning electron microscopy. Samples were also subjected to determination of porosity, water absorption and bulk density. Thermal and thermomechanical properties were determined by thermal analyses, refractoriness, refractoriness under load, thermal shock resistance and thermal dilatometric analysis with determination of thermal expansion coefficient. Mixtures with 10 wt.% and 20 wt.% of fly ash had the most promising results compared to alumina mixtures. Thermal shock resistance and modulus of rupture were improving with increasing content of aluminium oxide in the mixture.

Comparative Study on Nano-Structural and Traditional Al2O3-13TiO2 Air Plasma Sprayed Coatings and their Thermal Shock Performance

2017 ◽  
Vol 739 ◽  
pp. 103-107 ◽  
Author(s):  
Sun Hui Yao ◽  
Yan Liang Su ◽  
Hung Yu Shu ◽  
Chia I Lee ◽  
Zong Ling You
Keyword(s):  
Comparative Study ◽  
Thermal Shock ◽  
Raw Materials ◽  
Thermal Shock Test ◽  
Air Plasma ◽  
Cyclic Heat Treatment ◽  
Shock Test ◽  
Before And After ◽  
Nanostructural Coating ◽  
Plasma Sprayed

This paper reports a comparative study on characterization and thermal shock behavior of air plasma sprayed Al2O3-13wt.%TiO2 coatings using two kinds of raw materials, i.e. nanostructural and micro-structural (traditional) feedstock powders. The characterization, before and after thermal shock test, was carried out using micro-Vickers hardness tester, XRD and SEM. The thermal shock test was carried out using a water quenching method by employing cyclic heat treatment between ambient temperature and 650°C in air. The results showed that in spite of having denser structure, the nanostructural coating showed hardness a little lower than the traditional one at both conditions of before and after thermal shock tests. However, the nanostructural coating showed very good thermal shock behaviour.

Microstructure and Thermal Shock Behaviour of Alumina Composite Ceramic for Heat Transmission Pipeline

2014 ◽  
Vol 692 ◽  
pp. 217-223 ◽  
Author(s):  
Xiao Hong Xu ◽  
Xiao Yang Xu ◽  
Jian Feng Wu ◽  
Yang Zhou ◽  
De Zhi He
Keyword(s):  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Raw Materials ◽  
Composite Ceramic ◽  
Alumina Powder ◽  
Monoclinic Zirconia ◽  
Heat Transmission ◽  
Transmission Pipeline ◽  
Shock Resistance

Al2O3 composite ceramics materials used for heat transmission pipeline were prepared by pressureless sintering in air. Calcined bauxite, talc and commercial alumina powder were used as the main raw materials, partially stabilized zirconia was also added to improve the thermal shock resistance of the samples. The effects of composition and sintering temperature on density, phase composition, microstructure and thermal shock behavior of samples were evaluated. It shows that the B2 sample which was sintered at 1400 °C for 2 h has optimal properties with porosity 0.4%, bulk density 3.2 g•cm-3.The bending strength increases 19.46 MPa after 30 times thermal shock cycles from 1100 °C to room temperature. The main phases of B2 are corundum and spinel, meanwhile, a small amount of monoclinic zirconia and α-quartz are also detected according to XRD pattern. Microstructure analysis reveals that spinel crystals are interlocked by prismatic corundum crystals, bright white beaded monoclinic zirconia particles are distributed uniformly, and it is beneficial to improve the thermal shock resistance of sample.

Effect of Molar Ratio of Al2O3 to Fe2O3 on the Sintering and Thermal Shock Resistance of Al2O3-Fe2O3 Composite

2011 ◽  
Vol 194-196 ◽  
pp. 1745-1748
Author(s):  
Zhi Fa Wang ◽  
Jian Sheng Wang ◽  
Yue Jun Chen ◽  
Li Xue Yu ◽  
Jing Long Bu ◽  
...  
Keyword(s):  
Composite Materials ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Raw Materials ◽  
Sem Analysis ◽  
Molar Ratio ◽  
Alumina Powder ◽  
Linear Change ◽  
Shock Resistance

The Al2O3-Fe2O3 composite was prepared at 1550°C for 3h with alumina powder and ferric oxide powder as raw materials and with magnesia powder as additive. The effect of molar ratio of Al2O3 to Fe2O3 on the sintering and thermal shock resistance of the composite materials was studied. The results showed that the apparent porosity and bulk density of the samples both decreased with the molar ratio of Al2O3 to Fe2O3 increase, as a result, the linear change ratio and bending strength both increased. When the molar ratio of Al2O3 to Fe2O3 equals to 3, the sample exhibits excellent thermal shock resistance. The XRD and SEM analysis results indicated that the mechanical and thermal proprieties are relative to the microstructure and crystal phases of the composite materials.

scholarly journals The Effect of Class C Fly Ash on the Plasticity and Ageing of Ceramic Mixtures Based on Kaolin

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2761
Author(s):  
Radomir Sokolar ◽  
Martin Nguyen
Keyword(s):  
Fly Ash ◽  
Quartz Sand ◽  
Raw Materials ◽  
Ageing Time ◽  
Thermal Power ◽  
Initial Water Content ◽  
Green Body ◽  
Initial Water ◽  
Sand Mixture ◽  
Class C

The main aim of the presented article is to describe the behavior of class C fly ash—kaolin plastic doughs during the ageing process. Class C fly ash (CCFA) from the fluidized technology of fuel combustion in a thermal power plant was used as a non-plastic admixture to modify the plasticity in a kaolin–quartz sand mixture (for example, the base of a porcelain mixture). The ageing of plastic ceramic dough determined the effect of the CCFA admixture (0–10–20 wt. %) on the initial water content, plasticity (according to the Pfefferkorn test) and bulk density of a dried green body. The main feature of the CCFA admixture in the kaolin–quartz sand mixture is a solidifying effect. Fly ash increases the initial (mixing) water for the preparation of ceramic dough with constant plasticity (30 mm height of deformed cone Hf, according to the Pfefferkorn test), and Hf increases as the dough ages (the dough solidifies faster and loses its plasticity) with the addition of class C fly ash. The effect of CCFA addition on the plasticity and ageing of kaolin–quartz sand dough is documented on Bigot curves: higher content of fly ash decreases the drying shrinkage of the plastic dough, especially when drying samples that have been aged for 24 h in a plastic wrap (without the possibility of drying). The plastic dough’s ageing increases the porosity of the dried green body with increased content of CCFA in the raw materials mixture and increased ageing time.

scholarly journals Mechanical Properties of Aluminum/fly Ash Composites Produced by Hot Extrusion

2010 ◽  
Vol 7 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Subarmono. Subarmono ◽  
Jamasri. Jamasri ◽  
M. W. Wildan ◽  
Kusnanto. Kusnanto
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Wear Rate ◽  
Vickers Hardness ◽  
Bending Strength ◽  
Aluminum Matrix ◽  
Fine Powder ◽  
Hot Extrusion ◽  
Aluminum Matrix Composites ◽  
Green Body

This research aims to investigate mechanical properties of aluminum matrix composites reinforced with fly ash (AMC/Fly ash) produced using hot extrusion.AMC/Fly ash was prepared from aluminum fine powder as matrix and fly ash as reinforcement. The various amount of fly ash of 5%; 7.5%; 10%; 12.5% and 15% wt were added to the aluminum fine powder. Each composition was mixed using rotary mixer for 3 hours. The mixture was compacted using uniaxial pressing with a pressure of 100 MPa to produce green body. The green body was hot extruded with an extrusion ratio of 0.25 and temperature of 600ºC. Bending strength, Vickers hardness, wear rate and porosity of the AMC/fly ash were measured. The microstructure was observed using SEM. The results show that mechanical properties of the composites such as bending strength and Vickers hardness increase, porosity and wear rate decrease with increasing fly ash content up to 12.5 wt %. Above 12.5 wt % of fly ash those mechanical properties of composites seems to be inverse. The properties of AMC/12.5 wt % fly ash produced using hot extrusion from green body showing the best properties in term of the bending strength, Vickers hardness, porosity and wear resistance, that are 302 MPa; 79 VHN; 0.73 % and 0,0095 mg/(MPa.m), respectively.

Effect of Sheet Nanocarbon on Properties of Low Carbon Al2O3-C Refractories

2013 ◽  
Vol 745-746 ◽  
pp. 642-645
Author(s):  
Xiao Xian Wu ◽  
Hong Xia Li ◽  
Guo Qi Liu ◽  
Chong Chong Niu ◽  
Tian Fei Ma
Keyword(s):  
Thermal Shock ◽  
Milling Time ◽  
Raw Materials ◽  
Weight Ratio ◽  
Expanded Graphite ◽  
Heat Processing ◽  
Modulus Of Rupture ◽  
Thermal Shock Test ◽  
Low Carbon ◽  
Composite Powders

Sheet nanocarbon-Al2O3 composite powders were produced by vibratory milling using expanded graphite and Al2O3 powders as raw materials. The effect of different vibratory milling time on phase compositions and microstructure of the composite powders were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM). Then sheet nanocarbon-Al2O3 composite powders were used as additives to produce low carbon Al2O3-C refractories which had a carbon content of 6%. The results showed that about 50nm thickness sheet nanocarbon and Al2O3 composite powders were produced via 15h milling with expanded graphite to Al2O3 powders weight ratio of 1:2. With the increasing of milling time, the (002) diffraction peaks of graphite wear off gradually and nanosheet was desquamated from expanded graphite; It is beneficial to improve the bulk density, cold modulus of rupture (CMOR) and thermal shock resistance of Al2O3-C refractories when adding certain sheet nanocarbon-Al2O3 composite powders. The sample containing 0.5% sheet nanocarbon had a CMOR of 18.51MPa after 1000 °C heat processing in N2 atmosphere, while sample without adding any sheet nanocarbon was only 12.35MPa; The residual cold modulus of rupture (CMORTS) of sample containing 1% sheet nanocarbon was 4.22MPa after thermal shock test, while that of sample without nanocarbon was only 2.18MPa.

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