Comparison of Mineralogical Changes during Thermal Processing of Limestones

2017 ◽  
Vol 908 ◽  
pp. 56-60
Author(s):  
Dušan Dolák ◽  
Karel Dvořák ◽  
Jaroslav Bureš ◽  
Dominik Gazdič
Keyword(s):  
Thermal Treatment ◽  
Phase Transformations ◽  
Real Time ◽  
Thermal Processing ◽  
Industrial Process ◽  
Mineralogical Composition ◽  
Xrd Analysis ◽  
Laboratory Furnace ◽  
Different Temperatures

Thermal treatment of materials involves phase transformations. In the case of conventional laboratory furnace or in an industrial process, the samples are analysed after cooling. In this way, these phases can be monitored. A possible solution is non-ambient XRD analysis. Using HT-XRD analysis, it is possible to monitor the mineralogical composition at different temperatures in real time. The results of measurements on chemically precipitated limestone and limestone from the Cretaceous era show slight differences in temperature of decarbonation, but not clearly demonstrated the presence of unstable phases. This measurement, however, allowed the observation of a change in the size of the crystallites in the change of temperature.

The Influence of the Diffusion on Adherence of the 60T Deposits Obtained by Thermal Spraying in Electric Arc

2013 ◽  
Vol 371 ◽  
pp. 270-274 ◽  
Author(s):  
Stefan Lucian Toma ◽  
Diana Antonia Gheorghiu ◽  
Steluta Radu ◽  
Costică Bejinariu
Keyword(s):  
Thermal Treatment ◽  
Thermal Processing ◽  
Thermal Spraying ◽  
Xrd Analysis ◽  
Electric Arc ◽  
Processing Method ◽  
Thermal Treatments ◽  
Technological Parameters ◽  
Spraying Process

The physic-chemical and mechanical properties of steel deposits obtained by thermal spraying depend on technological parameters of the spraying process. Generally, wear resistance of the deposits depends on the degree of porosity and the adhesion of the layer to the substrate. In the case of the deposits obtained by spraying, studies have shown that between deposited layer (SD) and substrate (S) there are the following types of adhesions: mechanical, metallurgical, superficial, physical and diffusive. Each type of adherence, enumerated above, works through a well-defined mechanism so that it can be said that the adhesion of the obtained deposits by thermal spray is a sum of mechanisms which interacting. How these mechanisms interact, as well the percentage of the influence is determined by: operating parameters, by the deposit material and thermal treatments after the deposit obtaining. This paper proposes to determine the influence of thermal treatment on adherence of 60T deposits obtained by thermal spraying in electric arc- as a thermal processing method after metallization. The assessment of adherence deposit 60T - in two ways, according to with EN 582 and DIN 27201/2005 in conjunction with the investigations of electron microscopy (SEM), XRD analysis, and image analysis performed at both the zone: Coating - Interface - Substrate (CIS) has revealed the presence of diffusion and the structural constituents. The graphs of adherence variation for 60T deposits with the concentration gradient of the alloying elements of the 60T layer respectively of adherence layer (75B) obtained experimentally by investigations carried out on the substrate have demonstrated the role of the secondary thermal treatment on the deposit adherence.

Applications of On-Line XRF and XRD Analysis Techniques to Industrial Process Control

1988 ◽  
Vol 32 ◽  
pp. 49-57
Author(s):  
Mattt Hietala ◽  
Dennis J. Kalnicky
Keyword(s):  
Process Control ◽  
Real Time ◽  
Industrial Process ◽  
Xrd Analysis ◽  
Temperature Measurements ◽  
Flow Measurements ◽  
Analysis Techniques ◽  
On Line ◽  
Industrial Process Control ◽  
Assay Methods

Temperature, pressure, and flow measurements are considered standard for process control purposes. It is vital that they be made on-line in real-time and not manually in the laboratory. Chemical assays should be done as fast and continuous as temperature measurements in order to be useful for process control. Until recently, this has not been the case because the assay methods have been difficult to automate.

scholarly journals Mineralogical Composition and Physical–Mechanical Properties of Dasht-E-Taatrang Zar Sand Deposits (Afghanistan)

2020 ◽  
Vol 5 (1) ◽  
pp. 2
Author(s):  
Hemayatullah Ahmadi ◽  
Atal Yousufi ◽  
Amir Mohammad Mosazai
Keyword(s):  
Mechanical Properties ◽  
Construction Material ◽  
Mineralogical Composition ◽  
Xrd Analysis ◽  
Sample Collection ◽  
Extensive Field ◽  
Chemical And Mineralogical Composition ◽  
New City ◽  
Two Phases ◽  
Field Works

Sand is a common construction material used for various purposes, e.g., concrete, mortar, render, screed, and asphalt. The usage depends on its fineness, and its fineness is controlled by its mineralogical composition and physical-mechanical properties. This research aims to determine the chemical and mineralogical composition and the physical-mechanical properties of the Dasht-e-Taatrang Zar sand deposits within the Qarabagh and Bagram districts of Kabul and Parwan provinces in Afghanistan. To achieve the objectives of this research, a review of the existing literature has been combined with new extensive field works for macroscopic studies and sample collection, and laboratory analyses. In total, 23 samples during two phases of field works were collected and subjected to lab works for XRF, Schlich, and XRD analysis to determine the chemical and mineralogical composition; moreover, sieve and Atterberg analysis, specific gravity, soundness, and alkali-silica reaction tests were performed for characterization of the physical-mechanical properties of the studied samples. The results of the tests show that the Taatrang Zar sand deposits are considered as a suitable construction material, and due to their simple accessibility, the deposits have high potential as a construction material supplier for the Kabul new city project (Dehsabz) in Kabul and adjacent Parwan and Kapisa provinces.

Zirconium phase transformations observed by “in-situ” XRD analysis

Vacuum ◽  
2012 ◽  
Vol 86 (6) ◽  
pp. 785-788 ◽  
Author(s):  
Jan Riha ◽  
Pavol Sutta ◽  
Andrej Vincze ◽  
Rostislav Medlin
Keyword(s):  
Phase Transformations ◽  
Xrd Analysis ◽  
In Situ Xrd

scholarly journals Sonochemically synthetized ZnO-Graphene nanohybrids and its characterization

2020 ◽  
Vol 59 (1) ◽  
pp. 176-187 ◽  
Author(s):  
Cornel Cobianu ◽  
Niculae Dumbravescu ◽  
Bogdan-Catalin Serban ◽  
Octavian Buiu ◽  
Cosmin Romanitan ◽  
...  
Keyword(s):  
Thermal Treatment ◽  
Ph Value ◽  
Raman Band ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Carbon Incorporation ◽  
Additional Amount ◽  
Ph Increase ◽  
Compositional Properties ◽  
Crystalline Symmetry

AbstractThe paper presents the morphological, structural and compositional properties of the sonochemically prepared ZnO-1.4wt% Graphene (Z-G) nanocomposites as a function of pH value of suspension varying from 8.5 to 14 and thermal annealing at 450°C in nitrogen or air ambient. The SEM analysis of the Z-G hybrids dried at 150°C in air has shown a nano-flower like nanostructure for a pH value of 14. The XRD analysis of dried Z-G hybrids revealed a crystallite size increase from 3.5 nm to 18.4 nm with pH increase, and this result was explained in terms of colloids zeta potential evolution with pH value. The Raman and EDS spectroscopy have shown a split of the G band (1575 cm−1) of graphene into two bands (1575 cm−1 and 1605 cm−1), an increased height of D (1323 cm−1) band, and an additional amount of carbon due to CO2 absorption from the air, respectively. The carbon incorporation increased with the decrease of pH, and was associated with a hydrozincite phase, Zn5(CO3)2(OH)6. The formation of dried Z-G nanocomposite was clearly demonstrated only at a pH value equal to 14, where two ZnO Raman active bands at 314.9 cm−1 and 428.2 cm−1 appeared. This result may indicate the sensitivity of the Raman spectroscopy to the nanoflower-like nanostructure of dried Z-G hybrids prepared at pH=14. The thermal treatment of Z-G hybrids in N2at 450°C has increased the number of ZnO Raman bands as a function of pH value, it has decreased the amount of additional carbon by conversion of hydrozincite to ZnO and preserved the graphene profile. The thermal treatment in air at 450°C has increased the crystalline symmetry and stoichiometry of the ZnO as revealed by high and narrow Raman band from 99 cm−1 specific to Zn optical phonons, but it has severely affected the graphene profile in the Z-G hybrid, due to combustion of graphene in oxygen from the ambient.

CHARACTERIZATION OF HYDROXYAPATITE/TI6AL4V COMPOSITE POWDER UNDER VARIOUS SINTERING TEMPERATURE

2015 ◽  
Vol 75 (7) ◽  
Author(s):  
Amir Arifin ◽  
Abu Bakar Sulong ◽  
Norhamidi Muhamad ◽  
Junaidi Syarif
Keyword(s):  
Mechanical Properties ◽  
Composite Powder ◽  
Sintering Temperature ◽  
Physical And Mechanical Properties ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Different Temperatures ◽  
Two Phases ◽  
Work Interaction

Hydroxyapatite (HA) has been widely used in biomedical applications due to its excellent biocompatibility. However, Hydroxyapatite possesses poor mechanical properties and only tolerate limited loads for implants. Titanium is well-known materials applied in implant that has advantage in mechanical properties but poor in biocompatibility. The combination of the Titanium alloy and HA is expected to produce bio-implants with good in term of mechanical properties and biocompatabilty. In this work, interaction and mechanical properties of HA/Ti6Al4V was analyzed. The physical and mechanical properties of HA/Ti6Al4V composite powder obtained from compaction (powder metallurgy) of 60 wt.% Ti6Al4V and 40 wt.% HA and sintering at different temperatures in air were investigated in this study. Interactions of the mixed powders were investigated using X-ray diffraction. The hardness and density of the HA/Ti6Al4V composites were also measured. Based on the results of XRD analysis, the oxidation of Ti began at 700 °C. At 1000 °C, two phases were formed (i.e., TiO2 and CaTiO3). The results showed that the hardness HA/Ti6Al4V composites increased by 221.6% with increasing sintering temperature from 700oC to 1000oC. In contrast, the density of the composites decreased by 1.9% with increasing sintering temperature. 

Effect of Microstructural Characteristics of Electroless Nickel Metallisation on Solderability to Pb-Free Solder Alloys

2005 ◽  
Author(s):  
Changqing Liu ◽  
David A. Hutt ◽  
Dezhi Li ◽  
Paul P. Conway
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Bulk Composition ◽  
Industrial Process ◽  
Surface Characteristics ◽  
Electroless Nickel ◽  
X Ray ◽  
N2 Atmosphere ◽  
Different Temperatures ◽  
Free Solder

This paper aims to gain an insight into the correlation between the microstructure and surface composition of electroless Ni-P and its behaviour during soldering with Pb free alloys including Sn-3.8Ag-0.7Cu, Sn-3.5Ag and Sn-0.7Cu. Ni-P coatings with different P contents were produced through an industrial process on copper metal substrates. The surface morphology of these coatings was observed by Scanning Electron Microscopy (SEM) and the bulk composition was analyzed by means of Energy Dispersive X-ray analysis (EDX). The mechanical properties of the coatings were evaluated by nano-indentation testing under different maximum loads. However, to understand the behaviour of P in Ni-P coatings and deterioration of the coating surfaces during exposure to air, the surfaces of the coatings were also characterised by X-ray Photoelectron Spectroscopy (XPS) for storage at different temperatures. The dependence of the solderability of Ni-P coatings on the storage time and temperature was investigated by wetting balance testing, using an inactive or active flux with or without an inert N2 atmosphere. Finally, the solderability of Ni-P coatings to Pb free solders is correlated with their composition and microstructure (e.g. surface characteristics).

The Reactivity of CaTi4(PO4)6 with Alumina and Y-TZP Ceramics

2007 ◽  
Vol 361-363 ◽  
pp. 787-790
Author(s):  
Sabina Beranič Klopčič ◽  
Irena Pribošič ◽  
Tomaž Kosmač ◽  
Ute Ploska ◽  
Georg Berger
Keyword(s):  
Room Temperature ◽  
Xrd Analysis ◽  
Second Phase ◽  
Reaction Products ◽  
Stabilized Zirconia ◽  
Monoclinic Zro2 ◽  
Commercial Alumina ◽  
The Matrix ◽  
Different Temperatures ◽  
Edx Analyses

The reactivity of CaTi4(PO4)6 (CTP) with alumina and yttria-stabilized zirconia (Y-TZP) ceramics was studied. CTP powder was synthesized and composites with commercial alumina or zirconia matrices containing 10 wt% of CTP were prepared. They were sintered at different temperatures and characterized using XRD, SEM, and EDX analyses. The results showed that the alumina/CTP and Y-TZP/CTP composites start to react below 1000 °C. In the alumina/CTP composite the first reaction product, detected at 970 °C, was AlPO4. At temperatures above 1280 °C TiO2 and CaTiO3 were also formed and no CTP peaks could be detected using XRD analysis. The composite sintered at 1500 °C consisted of Al2O3 matrix, AlPO4, TiO2, CaTiO3 and Al2TiO5. The reaction products formed in the Y-TZP/CTP composite at 970 °C were TiO2 and Ca2Zr7O16. At higher sintering temperatures, 1280 °C and above, CTP was no longer present, Ca2Zr7O16 decomposed, forming CaO2 and ZrO2, and Y2O3 was consumed to form YPO4. Consequently, upon cooling to room temperature the matrix phase transformed to monoclinic ZrO2. Based on these results it can be concluded that CTP is not a suitable bioactive second phase for the fabrication of CTP composites with alumina or zirconia matrices.

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