Quality control of autoclaved aerated concrete by means of X-ray diffraction

The comparison of microstructure and mechanical properties between the autoclaved aerated concrete (AAC) and the autoclaved aerated concrete consist of sugar sediment (AAC-SS) was investigated in this work. The microstructure of AAC and AAC-SS was analyzed by the scanning electron microscopy (SEM). The mechanical properties of AAC and AAC-SS were focused on the compressive strength, the density, the water absorption and the flexural strength. To comfirm the tobermorite phase, the phase formation of the samples was tested using X-ray diffraction (XRD). It was found that the microstructure of AAC and AAC-SS surface was the finer needle-like crystalline morphology. The compressive strength (5.9 N/mm2) and flexural strength (1.82 N/mm2) of AAC-SS were higher than that of the AAC (5.0 N/mm2 and 1.64 N/mm2). While, the value of density (0.60 g/cm3) and humidity (23.59%) of AAC-SS had little less than that of the AAC (0.61 g/cm3 and 24.11%). The increasing of the tobermorite phase, which was added by the sugar sediment, had affected to the improvement of the mechanical properties. The specimens of both AAC and AAC-SS were claimed in quality class of 4, which based on the Thai Industrial Standard 1505-1998.

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Utilization of Desulfuration Residues in Non-Autoclaved Aerated Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.707 ◽

2011 ◽

Vol 250-253 ◽

pp. 707-710

Author(s):

Fang Xian Li ◽

You Zhi Chen ◽

Qi Jun Yu ◽

Jiang Xiong Wei

Keyword(s):

Compressive Strength ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Bulk Density ◽

Hydration Products ◽

X Ray Diffraction ◽

X Ray ◽

Autoclaved Aerated Concrete ◽

Aerated Concrete ◽

Scanning Electron

Desulfuration residues were used as aggregate to produce Non-autoclaved aerated concrete. The effects of water-hinder ratio, casting temperature on the gas forming behavior, and those of desulfuration residue content on the compressive strength and bulk density of aerated concrete were investigated. The types of the hydration products and the microstructure of Non-autoclaved aerated concrete with desulfuration residue were investigated by means of X-ray diffraction and scanning electron microscope. Results show that the optimum replacement amount was determined as 50% and at this rate the compressive strength, bulk density of Non-autoclaved aerated concrete were measured as 2.83 MPa and 543 kg/m3. The hydration products of Non-autoclaved aerated concrete with desulfuration residue are C2SH (A) and C2SH (B) along with ettringite and hydrogarnet phases.

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In situ time-resolved X-ray diffraction of tobermorite formation in autoclaved aerated concrete: Influence of silica source reactivity and Al addition

Cement and Concrete Research ◽

10.1016/j.cemconres.2011.01.022 ◽

2011 ◽

Vol 41 (5) ◽

pp. 510-519 ◽

Cited By ~ 70

Author(s):

Kunio Matsui ◽

Jun Kikuma ◽

Masamichi Tsunashima ◽

Tetsuji Ishikawa ◽

Shin-ya Matsuno ◽

...

Keyword(s):

X Ray Diffraction ◽

Time Resolved ◽

X Ray ◽

Autoclaved Aerated Concrete ◽

Silica Source ◽

Aerated Concrete ◽

Al Addition

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Study of the influence of the secondary raw materials on microstructure and properties of calcium silicate composite

The proceedings of the 13th international conference "Modern Building Materials, Structures and Techniques" (MBMST 2019) ◽

10.3846/mbmst.2019.129 ◽

2019 ◽

Author(s):

Jana Húšťavová ◽

Vít Černý ◽

Rostislav Drochytka

Keyword(s):

Calcium Silicate ◽

Raw Materials ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Autoclaved Aerated Concrete ◽

Secondary Raw Materials ◽

Aerated Concrete ◽

The Difference ◽

Positive Effect

Calcium silicate composites are a widely used building material, especially autoclaved aerated concrete or sand-lime bricks. The physico-mechanical properties of these materials depend on their microstructure. Microstructure is characterized by the content of crystalline calcium silicate compounds that arise during autoclaving. This is in particular the tobermorite mineral, which carries the mechanical strength of the composite. This paper focuses on the influence of secondary raw materials on properties and microstructure of the calcium silicate composite. Secondary raw materials were selected as slag from the combustion of lignite and ground glass. Mixtures of composites were selected with respect to the required C/S molar ratio of 0.73. The hydrothermal treatment was carried out at a temperature of 190 °C and a residence time of 4, 8 and 16 hours. The microstructure of calcium silicate composites and autoclaved aerated concrete was studied. The use of slag resulted in an increase in the intensity of the diffraction line of tobermorite by X-ray diffraction analysis as well as the use of glass. The difference was particularly evident in the shape of the tobermorite crystals. Long strong crystals were detected in the sample with slag, while the sample with glass exhibited low tobermorite leaves. Porous structure of autoclaved aerated concrete with slag was uniform, unlike samples with glass. Both materials have a positive effect on the increase in compressive strengths of the samples.

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Heavy Mineral Sands Mining and Downstream Processing: Value of Mineralogical Monitoring Using XRD

Minerals ◽

10.3390/min11111253 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1253

Author(s):

Uwe König ◽

Sabine M. C. Verryn

Keyword(s):

Quality Control ◽

High Speed ◽

Direct Analysis ◽

Downstream Processing ◽

Heavy Mineral ◽

X Ray Diffraction ◽

Mineral Concentration ◽

X Ray ◽

Tio2 Anatase ◽

Titania Slag

Heavy mineral sands are the source of various commodities such as white titanium dioxide pigment and titanium metal. The three case studies in this paper show the value of X-ray diffraction (XRD) and statistical methods such as data clustering for process optimization and quality control during heavy mineral processing. The potential of XRD as an automatable, reliable tool, useful in the characterization of heavy mineral concentrates, product streams and titania slag is demonstrated. The recent development of ultra-high-speed X-ray detectors and automated quantification allows for ‘on the fly’ quantitative X-ray diffraction analysis and truly interactive process control, especially in the sector of heavy mineral concentration and processing. Apart from the information about the composition of a raw ore, heavy mineral concentrate and the various product streams or titania slag, this paper provides useful information by the quantitative determination of the crystalline phases and the amorphous content. The analysis of the phases can help to optimize the concentration of ores and reduction of ilmenite concentrate. Traditionally, quality control of heavy mineral concentrates and titania slag relies mainly on elemental, chemical, gravimetrical, and magnetic analysis. Since the efficiency of concentration of minerals in the different product streams and reduction depends on the content of the different minerals, and for the latter on the titanium and iron phases such as ilmenite FeTiO3, rutile TiO2, anatase TiO2, or the various titanium oxides with different oxidation stages, fast and direct analysis of the phases is required.

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In situ monitoring of hydrothermal reactions by X-ray diffraction with Bragg–Brentano geometry

Journal of Applied Crystallography ◽

10.1107/s1600576720006019 ◽

2020 ◽

Vol 53 (4) ◽

pp. 1163-1166

Author(s):

Karsten Mesecke ◽

Winfried Malorny ◽

Laurence N. Warr

Keyword(s):

Quantitative Information ◽

In Situ Monitoring ◽

X Ray Diffraction ◽

Hydrothermal Conditions ◽

X Ray ◽

Saturated Vapour Pressure ◽

Concrete Production ◽

Aerated Concrete ◽

Kinetics Of

This note describes an autoclave chamber developed and constructed by Anton Paar and its application for in situ experiments under hydrothermal conditions. Reactions of crystalline phases can be studied by successive in situ measurements on a conventional laboratory X-ray diffractometer with Bragg–Brentano geometry at temperatures <483 K and saturated vapour pressure <2 MPa. Variations in the intensity of X-ray diffraction reflections of both reactants and products provide quantitative information for studying the reaction kinetics of both dissolution and crystal growth. Feasibility is demonstrated by studying a cementitious mixture used for autoclaved aerated concrete production. During a period of 5.7 h at 466 K and 1.35 MPa, the crystallization of torbermorite and the partial consumption of quartz were monitored.

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Quality control in urinary stone analysis: results of 44 ring trials (1980–2001)

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2005.051 ◽

2005 ◽

Vol 43 (3) ◽

Cited By ~ 50

Author(s):

Albrecht Hesse ◽

Rolf Kruse ◽

Wolf-Jochen Geilenkeuser ◽

Matthias Schmidt

Keyword(s):

Quality Control ◽

Infrared Spectroscopy ◽

Urinary Stone ◽

Error Rates ◽

The Body ◽

X Ray Diffraction ◽

Stone Analysis ◽

Chemical Methods ◽

X Ray ◽

Pure Substances

AbstractUrinary stone analysis is the most important diagnostic step after stone removal from the body. The methods employed for these analyses are based on diverse analytical principles. Chemical methods are used for detecting individual ions. Infrared spectroscopy is used for examining molecular structures, and X-ray diffraction for determination of the crystalline structure of a substance. Since 1980, a twice-yearly ring trials quality control survey has been on offer to examine the quality of urinary stone analyses. A summary of the results of 44 ring trials (1980–2001) has been compiled for individual pure substances and binary (two-component) mixtures. On average, 100 laboratories have participated in these ring trials. Initially, over 80% of the participants carried out their analyses using chemical methods. In 2001, this figure decreased to a mere 13%. In contrast, a progressive increase in the use of infrared spectroscopy was observed, up to 79% of all participants employed this method. X-Ray diffraction was only employed in a small number of specialised laboratories (5–9%). The chemical methods produced a very high proportion of errors (6.5–94%) with both the pure substances and binary mixtures, whereas high error rates for infrared spectroscopy and X-ray diffraction were confined to individual substances only. Due to the poor results in the ring trials, the majority of laboratories stopped using chemical analysis, which is now considered to be obsolete. Regarding mixtures, error rates of over 10% also occurred with infrared spectroscopy and X-ray diffraction. Ring trials are indispensable for the quality management of urinary stone analysis.

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Influence of Gypsum Additive on the Formation of Tobermorite in Autoclaved Aerated Concrete

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.714.116 ◽

2016 ◽

Vol 714 ◽

pp. 116-121 ◽

Cited By ~ 1

Author(s):

Ester Helanova ◽

Rostislav Drochytka ◽

Vit Cerný

Keyword(s):

Chemical Composition ◽

Hydrothermal Reaction ◽

Raw Materials ◽

Fly Ashes ◽

Sem Images ◽

X Ray ◽

Autoclaved Aerated Concrete ◽

Variable Chemical ◽

Aerated Concrete

The quality of the aerated concrete strongly depends on the chemical composition of the raw materials, as well as the process of the hydrothermal reaction during autoclaving. Due to the variable chemical composition of fly ashes, it is necessary to identify the effect of each ion on the formation of the microstructure of aerated concrete. This paper examines the process of formation of tobermorite with the addition of sulphates in various percentage representation. The microstructure of aerated concrete is assessed using SEM images and the mineralogical by means of X-ray analysis.

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Kontrol Kualitas Uang Logam Pecahan Rp 1.000,00 dengan Teknik Difraksi Sinar-X (XRD)

Metal Indonesia ◽

10.32423/jmi.2020.v42.11-19 ◽

2020 ◽

Vol 42 (1) ◽

pp. 11

Author(s):

Ibrahim Purawiardi

Keyword(s):

Quality Control ◽

Structural Defect ◽

Special Technique ◽

X Ray Diffraction ◽

X Ray ◽

Analytical Technique ◽

Standard Quality ◽

Production Target

Uang logam pecahan Rp 1.000,00 merupakan salah satu uang dengan nilai intrinsik yang paling baik dan banyak beredar di masyarakat. Oleh karena penggunaannya yang tinggi, maka kualitas uang logam ini perlu diperhatikan. Kontrol kualitas pecahan uang logam ini perlu dilakukan agar pecahan yang beredar di masyarakat adalah pecahan uang logam yang memenuhi standar. Salah satu cara yang dapat dilakukan untuk mengontrol kualitasnya adalah dengan teknik difraksi sinar-x (XRD). Dengan teknik ini, cacat struktur dapat dideteksi tanpa harus merusak uang logamnya, sehingga uang logam yang cacat struktur dapat dieliminasi dari peredaran. Namun, teknik XRD memerlukan cara tersendiri untuk menginterpretasikannya, oleh karena itu studi ini dilakukan untuk mencontohkan bagaimana cara menginterpretasikannya. Lima buah sampel uang logam pecahan Rp 1.000,00 digunakan dalam studi ini, dimana dari hasil kontrol kualitas yang dilakukan, terdapat satu pecahan uang logam yang terdapat cacat struktur. Dari hasil studi sendiri menunjukkan bahwa kelima sampel memiliki karakteristik struktur FCC yang merupakan target produksi dengan indikator bidang-bidang (111), (200), (220) dan (311). Namun, salah satu sampel ternyata memiliki cacat produksi berupa munculnya karakteristik BCC yang bukan merupakan target produksi dengan indikator bidang (310). Sampel yang memiliki cacat produksi ini dapat direkomendasikan untuk tidak diedarkan. Dari studi ini terbukti bahwa teknik analisis XRD dapat digunakan secara efektif untuk mengontrol kualitas uang logam secara non-destruktif. The IDR 1000 coin is one of the best intrinsic rupiah money and most widely used by Indonesian people. Because of these reasons, the quality of it needs to be considered. The quality control of this coin must be done in order to make sure that it meets the standard quality to distribute. An x-ray diffraction (XRD) technique is one way in order to control the quality of this coin. By using this technique, structural defect on this coin can be detected without destructs it, so that defected coin can be rejected to be distributed. However, this technique needs special technique to interpret it. This study aimed to exemplify how to interpret it. Five IDR 1000 coins were used as samples in this study. From this study, the result shows that there is a coin with structural defect. The results of this study show that all of five samples have FCC characteristics as a production target with (111), (200), (220) and (311) planes as indicators. However, there is a sample with a production defect i.e. BCC characteristics with (310) plane as an indicator. This sample were then recommended to be rejected. Overall, this study shows that this XRD analytical technique can be effectively used for controlling the quality of money coin without destructs it.

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