Electron fractographic and x-ray studies of fractures in test pieces with stress concentrators, broken at various speeds and temperatures

1975 ◽  
Vol 10 (3) ◽  
pp. 331-333
Author(s):  
Z. G. Dutsyak ◽  
S. Ya. Yarema ◽  
Z. M. Manyuk ◽  
Yu. I. Babei
Keyword(s):  
Stress Concentrators ◽  
X Ray ◽  
Test Pieces

Effect of Dispersant Addition on Properties of Ceramic Pieces from Kampung Dengir, Besut, Terengganu, Malaysia

2017 ◽  
Vol 888 ◽  
pp. 28-32
Author(s):  
Noor Asliza Ismail Adnen ◽  
Nur Atiqah Azwa Joulme Morad ◽  
Mohd Aidil Adhha Abdullah ◽  
Mohd Al Amin Muhamad Nor
Keyword(s):  
Water Absorption ◽  
Rheological Behavior ◽  
Ceramic Body ◽  
X Ray ◽  
Test Pieces ◽  
Ceramic Slurry ◽  
Sample Characterization ◽  
Ball Clay ◽  
Good Flow

The abundancy of ball clay can be transform into more useful form. This study was conducted to investigate the effect of different amount of dispersant on ceramic system. Ball clay from Kampung Dengir, Besut, Terengganu was used as starting powder while sodium silicate was used as dispersant to produce good flow ability, minimum viscosity and controllable ceramic slurry. Ceramic slurry was prepared by adding additives such as binder, flux, filler and dispersant, casted onto POP mould to obtain ceramic body. Ceramic then cut into test pieces (8cm x 2cm) and mixed for 2 h and aged for 2 days before dried at 70 °C overnight and sintered at temperature of 800-1200 °C in furnace for 2 h with heating rate 5 °C/min. Slurries also tested for rheological properties using rheometer (brand Thermo Haake). Viscosity and shear stress were measured to investigate the rhoelogical behaviour of slip with different amount of dispersant (0.03 mL to 0.06 mL/200 mL of sample). Characterization of raw samples has been done using X-ray diffractometer (XRD) showing the presence of kaolinite and quartz. Effect of dispersant on rheological behavior, rate of shrinkage, water absorption, porosity and density were investigated It was found that increase in amount of dispersant added exhibit the best rheological behavior, and 0.05 mL dispersant was the optimum amount in term of rate of shrinkage, water absorption, porosity and density. As a conclusion, 0.05 mL was the optimum dispersant which gives best rheological behavior and almost fault-free ceramic bodies

Preliminary evaluation of the physical properties of red ceramic incorporated with solid residue

MRS Advances ◽  
2018 ◽  
Vol 3 (61) ◽  
pp. 3575-3579
Author(s):  
Francine M. Nunes ◽  
Eduarda M. Rangel ◽  
Fernando M. Machado ◽  
Rubens Camaratta ◽  
Letícia P. Cardoso ◽  
...  
Keyword(s):  
Physical Properties ◽  
Linear Shrinkage ◽  
Raw Material ◽  
Preliminary Evaluation ◽  
Solid Residue ◽  
X Ray Diffraction ◽  
Linear Contraction ◽  
X Ray ◽  
Test Pieces ◽  
Renewable Raw Material

AbstractThe food processing industry highlights the daily generation of large amounts of eggshell solid residue. In this way, this residue becomes a non renewable raw material to be reused as an additive in red ceramics, in order to reduce the volume of disposal to the environment and improve the physical properties of the product. The objective of this work was to evaluate the forming moisture, linear shrinkage of drying and shrinkage of drying burning of ceramic test pieces (CS’s) with formulations with 2% and 3% of white eggshell residue (ER) incorporated in clay. The clay and ER were collected in the city of Pelotas-RS. The ER sample was analyzed by X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD). After pressing, natural and artificial drying was carried out and the CS’s were burned. These were evaluated through normative parameters C-020/95, C-021/95 and C-026/95. The values obtained for the forming moisture were between 5.82 and 8.78%, for the linear shrinkage of drying between 0.10 and 0.43% and, for the linear contraction burning between -0.29 and 0.08%. The results showed that the addition of ER to the ceramic mass helped in the reduction of the forming moisture and the linear shrinkage of the ceramic test pieces.

scholarly journals Effect of iron mining tailings as a red ceramic additive for decreased sintering temperature

2020 ◽  
Vol 25 (4) ◽  
Author(s):  
Igor Brumano Coelho Amaral ◽  
Bernat Vinolas Prat ◽  
Arlete Barbosa dos Reis
Keyword(s):  
Raw Materials ◽  
Mineralogical Composition ◽  
Ceramic Materials ◽  
Linear Shrinkage ◽  
Burning Temperature ◽  
X Ray ◽  
Burning Process ◽  
Test Pieces ◽  
Energy Expense ◽  
Different Temperatures

ABSTRACT The ceramic materials industry includes the burning process at high temperatures in a way that the energy expense of the conventional methods of burning is very high. Using alternative raw materials shows a large potential in this process, such as wastes from other industrial processes, which may reduce the burning temperature of the ceramics, providing desirable characteristics with lower energy expense, as additives that have a high fluxes content, such as iron ore tailings. The waste used had its chemical composition analyzed by X-Ray Fluorescence, mineralogical composition analyzed by X-ray Diffraction and Granulometry by sieving and sedimentation. To study the properties of ceramic test pieces with addition of wastes, we used three different temperatures in the burning process to test if the use of the waste could improve its characteristics. We produced test pieces including a mixture of soil with 10 and 20% content of waste exposed to the sintering process at temperatures of 750, 850 and 950° C. To test the technological properties of the pieces we performed tests of linear shrinkage, loss on fire, coloring, water absorption, apparent porosity, compressive strength and scanning electron microscopy. The color of the test pieces was intensified, and the tested characteristics that showed improvements when the burning temperature decreased. However, at defined concentrations there was little variation in the test pieces produced with pure soil.

scholarly journals Environmental assessment of sulfidic mine waste and its integration into green construction materials

2021 ◽  
Author(s):  
Jillian Helser ◽  
Valérie Cappuyns
Keyword(s):  
Mine Drainage ◽  
Mine Waste ◽  
Construction Materials ◽  
Economic Benefits ◽  
Leaching Tests ◽  
Case Scenario ◽  
Worst Case ◽  
X Ray ◽  
Green Construction ◽  
Test Pieces

<p>Proper management and storage of mine waste (e.g., tailings and waste rock) is one of the main issues that mining industries face. Additionally, there is already an uncountable amount of existent historical mine waste, which may, even centuries later, still be leaching contaminants into the environment. One solution to minimize the risks associated with the waste, with also potential economic benefits, is through the valorization of the waste. This can be done by first recovering valuable metals and removing hazardous contaminants. Then, the remaining residue can be valorized into green construction materials, such as geopolymers, ceramics or cement.  For some mine waste materials, such as those with only trace levels of metals, that are not economically viable to extract, the “waste” can be reused directly without this additional cleaning step. In the present study, mine waste originating from 3 different sites, both operational and historical mines, was characterized and assessed in comparison with the cleaned mine waste (i.e., cleaned by bioleaching or ion flotation methods) and with different types of green construction materials containing (cleaned and uncleaned) mine waste. Particular emphasis was given to the study of the mobilization of metal(loid)s from the mine waste and green construction materials (i.e., ceramics, geopolymers and cement) under different conditions, through a series of leaching tests (i.e., EN 12457-2, US EPA’s Toxicity Characteristic Leaching Procedure, and a pH-dependent leaching test). The standardized leaching tests were applied to either mimic neutral conditions in nature, conditions in a landfill (end of life), or a worst-case scenario (i.e., in extremely acidic or alkaline pH).</p><p>Mineralogical (X-ray diffraction) and chemical (X-ray fluorescence) characterizations of the original mine waste samples revealed high levels of Pb, Zn, and As in most samples. Additionally, the samples consisted mostly of quartz, micas, clay minerals and/or feldspars. Some samples also contained pyrite (FeS<sub>2</sub>), a key mineral that generates acid mine drainage. Based on the leaching studies, some geopolymers, ceramics, and cement efficiently immobilized certain metals (such as Pb and Zn). Also, longer curing durations of the geopolymers in most cases improved the immobilization of metal(loid)s. Overall, the leaching studies revealed that the concentrations of mine waste incorporated in the construction materials, as well as the pH of those materials, were the main factors influencing the mobility of metal(loid)s. Additionally, for ceramics, the temperature at which the test pieces were fired, also played a major role. Through this detailed characterization, the environmental impacts were assessed from the mine waste to the downstream products, determining which valorization methods are the most viable to close the circular economy loop.</p>

Enamel Development and Application on the Pottery of Icoaraci

2012 ◽  
Vol 727-728 ◽  
pp. 681-685
Author(s):  
Andre Wilson da Cruz Reis ◽  
Marlice Cruz Martelli ◽  
Roberto de Freitas Neves
Keyword(s):  
Raw Materials ◽  
Ceramic Body ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Test Pieces ◽  
The Village

The development of technology for the application of enamels on pieces of red pottery, in the handicraft sector, is an alternative to improve the quality of the ceramic body forming a waterproof layer that serves as a protection when used for foods and also to add a decorative effect and increase commercial value. This work develops an enameling technique in the production conditions of the artisans in the village of Icoaraci-PA/Brazil. The characterization of raw materials was performed by X-ray fluorescence, X-ray diffraction, particle size analysis, Thermogravimetric and Differential Thermal Analysis. Steps for enamel preparation using commercial transparent frit and bottle glass, and the technique for applying the glaze and firing are presented. The results for the test pieces were very good with the application of transparent frit fired at 900 ° C for 3 hours.

Casting Defects Analysis Making the Best Use of High-Energy X-Ray CT

2005 ◽  
Author(s):  
Shouhei Numata ◽  
Tatsurou Yashiki ◽  
Noriyuki Sadaoka
Keyword(s):  
Measurement Method ◽  
Three Dimensional ◽  
High Energy ◽  
Casting Defects ◽  
Ct Reconstruction ◽  
X Ray ◽  
Test Pieces ◽  
Cavity Measurement ◽  
Voxel Value ◽  
Shrinkage Cavities

A novel method of analyzing casting defects such as shrinkage cavities by utilizing high-energy x-ray computed tomography (CT) has been developed. The method was realized as the module of three-dimensional (3-D) bitmap CAD software StereoCooker for utilizing x-ray CT images. The cavity measurement method was based on the defocusing feature of an x-ray CT image. The authors assumed the defocusing to Gaussian, and therefore the diameter of the cavity could be calculated from the summation of the voxel value profile of the cavity and the circumference. The Gaussian defocusing hypothesis was confirmed by the CT reconstruction simulation with an accuracy higher than 10% for the conditions of the actual x-ray CT apparatus. The cavity measurement method was verified by applying it to cavity test pieces. The test pieces had cavity diameters of 0.5, 0.6, 0.7, 0.8 and 1.0mm. Using the rotate-only mode of the 6MeV x-ray CT, cavities of 0.6mm or greater in diameter could be detected. The accuracy of the cavity size is higher than 0.1mm for diameters of 0.7mm and greater. The verification of simulation by a comparison of the defects predicted by a simulation and those measured by this method has been proposed.

scholarly journals Tensile tests of crystals of an aluminium zinc alloy

1925 ◽  
Vol 109 (749) ◽  
pp. 143-149 ◽  
Keyword(s):  
Heat Treatment ◽  
Solid Solution ◽  
Surface Layer ◽  
Tensile Tests ◽  
Zinc Alloy ◽  
Pure Aluminium ◽  
Cubic Symmetry ◽  
X Ray ◽  
Test Pieces ◽  
Small Test

By the method of straining and heat treatment large crystals were grown in an alloy of aluminium containing 18·6 per cent. zinc. This alloy is very near the limit of solubility of zinc in aluminium, but the microstructure showed it to be a solid solution. The most favourable extension was 1 per cent., with a load of 12·2 tons per square inch. The crystals were not so large as those obtained for pure aluminium, rarely exceeding 2 inches in length and 0·5 inch in diameter. They were frequently covered with a surface layer of smaller crystals of varying size. These were removed by machining. Small test pieces were made varying in length from 1 to 2 inches over the parallel portion and having a diameter of from 0·05 to 0·25 inch. The crystals gave excellent X-ray reflections. The structure appears to be similar to pure aluminium, but has a slightly larger lattice, viz., 4·18 Å compared with 4·06 Å for pure aluminium. Reflections from both cubic and octahedral planes were obtained. The angles calculated between each pair of planes showed that the crystals had cubic symmetry.

Improving the Properties of Low Temperature Sintered Alumina Bodies with Granite Reject Additions

2006 ◽  
Vol 45 ◽  
pp. 2212-2217
Author(s):  
Wilson Acchar ◽  
G.C.L. Silveira ◽  
Sonia Regina Homem de Mello-Castanho ◽  
Ana M. Segadães
Keyword(s):  
Low Temperature ◽  
Manganese Oxide ◽  
Industrial Waste ◽  
Raw Materials ◽  
Industrial Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ornamental Stone ◽  
Test Pieces ◽  
Potential Use

The use of industrial waste materials as additives in the manufacture of ceramic products has been attracting a growing interest from researchers in recent years and is becoming common practice. The continued depletion of natural resources throws a new light on the potential use of some industrial wastes and natural sub-products as full-fledged alternative ceramic raw materials. This work describes the research carried out on the low temperature manufacturing of alumina bodies using, as additive, granite reject as-produced by an ornamental stone processing industry that saws granite stones into blocks and slabs in Rio Grande do Norte, Brazil. This reject is produced in significant amounts and is discarded in sedimentation lagoons, landfill areas or simply thrown in rivers, resulting in environmental pollution. Samples containing up to 30 wt% granite reject and 5 wt% manganese oxide (constant) were uniaxially pressed and sintered in air in an electric furnace (1150-1350 °C, for 1 hour). Sintered test pieces were characterized by X-ray diffraction, apparent density, open porosity and flexural strength. The results showed that the addition of granite reject and manganese oxide enables low temperature sintering and remarkably improves the cold mechanical properties of the alumina body.

Space and Time Distribution of Hard X-Ray Emission in a Loop at the Beginning of a Flare

1994 ◽  
Vol 144 ◽  
pp. 275-277
Author(s):  
M. Karlický ◽  
J. C. Hénoux
Keyword(s):  
Time Distribution ◽  
Electron Bombardment ◽  
Spatial Evolution ◽  
Superthermal Electrons ◽  
Flare Loop ◽  
X Ray ◽  
Superthermal Electron ◽  
Flare Loops ◽  
Chromospheric Evaporation ◽  
Temporal And Spatial

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

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