scholarly journals Genesis of langrial iron ore of hazara area, khyber pakhtunkhaw, parkistan

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Naghmah Haider1 ◽  
Sajjad Khan1 ◽  
Rehanul Haq Siddiqui2 ◽  
Shahid Iqbal3 ◽  
Nazar-Ul -Haq1

The Iron Ore of Hazara area has been studied at seven locations for detail mineralogical and genesis investigations. Thick bedded iron ore have been observed between Kawagarh Formation and Hangu Formation i.e Cretaceous-Paleocene boundary. At the base of Hangu Formation variable thickness of these lateritic beds spread throughout the Hazara and Kohat-Potwar plateau. This hematite ore exists in the form of unconformity. X-Ray Diffraction technique (XRD), X-ray Fluorescence Spectrometry (XRF), detailed petroghraphic study and Scanning Electron Microscope (SEM) techniques indicated that iron bearing minerals  are hematite,  chamosite and  quartz, albite, clinochlore, illite-montmorillonite, kaolinite, calcite, dolomite and ankerite are the impurities present in these beds. The X-ray Fluorescence (XRF) results show that the total Fe2O3 ranges from 39 to 56% and it has high silica and alumina ratio is less than one. Beneficiation requires for significant increase in ore grade. The petroghraphic study revealed the presence of ooids fragments as nuclei of other ooids with limited clastic supply which indicate high energy shallow marine depositional setting under warm and humid climate. The overall results show that Langrial Iron ore is a low-grade iron ore and can be upgraded up to 62% by applying modern mining techniques to fulfill steel requirements of the country.

2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Naghmah Haider ◽  
Sajjad Khan ◽  
Rehanul Haq Siddiqui ◽  
Shahid Iqbal ◽  
Nazar-Ul -Haq

The Iron Ore of Hazara area has been studied at seven locations for detail mineralogical and genesis investigations. Thick bedded iron ore have been observed between Kawagarh Formation and Hangu Formation i.e Cretaceous-Paleocene boundary. At the base of Hangu Formation variable thickness of these lateritic beds spread throughout the Hazara and Kohat-Potwar plateau. This hematite ore exists in the form of unconformity. X-Ray Diffraction technique (XRD), X-ray Fluorescence Spectrometry (XRF), detailed petroghraphic study and Scanning Electron Microscope (SEM) techniques indicated that iron bearing minerals  are hematite,  chamosite and  quartz, albite, clinochlore, illite-montmorillonite, kaolinite, calcite, dolomite and ankerite are the impurities present in these beds. The X-ray Fluorescence (XRF) results show that the total Fe2O3 ranges from 39 to 56% and it has high silica and alumina ratio is less than one. Beneficiation requires for significant increase in ore grade. The petroghraphic study revealed the presence of ooids fragments as nuclei of other ooids with limited clastic supply which indicate high energy shallow marine depositional setting under warm and humid climate. The overall results show that Langrial Iron ore is a low-grade iron ore and can be upgraded up to 62% by applying modern mining techniques to fulfill steel requirements of the country.


2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Naghmah Haider ◽  
Sajjad Khan ◽  
Rehanul Haq Siddiqui ◽  
Shahid Iqbal ◽  
Nazar UI-Haq

In this paper, a detailed mineralogical and genesis investigation have been carried out in the seven locations of the Iron Ore in Hazara area. Thick bedded iron ore have been observed between Kawagarh Formation and Hangu Formation i.e, Cretaceous-Paleocene boundary. At the base of Hangu Formation, variable thickness of these lateritic beds spread throughout the Hazara and Kohat-Potwar plateau. This hematite ore exists in the form of unconformity. X-ray diffraction technique (XRD), X-ray fluorescence spectrometry (XRF), detailed petroghraphic study and scanning electron microscope (SEM) techniques indicated that those iron bears minerals including hematite, chamosite and quartz, albite, clinochlore, illite-montmorillonite, kaolinite, calcite, dolomite, whereas ankerite are the impurities present in these beds. The X-ray fluorescence (XRF) results show that the total Fe2O3 ranges from 39 to 56%, with high silica and alumina ratio of less than one. Beneficiation requires for significant increase in ore grade. The petroghraphic study revealed the presence of ooids fragments as nuclei of other ooids with limited clastic supply, which indicate high energy shallow marine depositional setting under warm and humid climate. The overall results show that Langrial Iron Ore is a low-grade iron ore which can be upgraded up to 62% by applying modern mining techniques so as to fulfill steel requirements of the country.


2021 ◽  
Vol 1 ◽  
pp. 69-70
Author(s):  
Rebecca Kühn ◽  
Michael Stipp ◽  
Bernd Leiss

Abstract. The physical properties of claystones, shales, and slates are highly dependent on the alignment of phyllosilicate minerals. With increasing overburdening, the shape and the crystallographic preferred orientation of these minerals are affected by uniaxial shortening as well as tectonic processes including recrystallization under elevated pressure and temperature conditions. The microstructural anisotropy expressed mainly by the alignment of phyllosilicates significantly predetermines the orientation of fractures, hence the shear strength and stability of clay-rich sediments and rocks. A quantitative analysis of phyllosilicate alignment is therefore essential to evaluate the properties and the mechanical behavior of these rocks. This can be carried out by analyzing the crystallographic preferred orientation (texture). Although texture analysis is a common tool in geosciences, it becomes more difficult in fine-grained rocks owing to for example particle size, heterogeneity, the polyphase composition, and difficulties in sample preparation. Methods such as electron backscatter diffraction, neutron diffraction, or laboratory X-ray diffraction are restricted with respect to preparation artifacts, sampling size and statistics, water content, etc. To overcome these issues, we successfully apply high-energy X-ray diffraction as available at synchrotron research facilities, e.g., at the German Electron Synchrotron Facility (DESY) in Hamburg, Germany, or the European Synchrotron Research Facility (ESRF) in Grenoble, France. In combination with Rietveld refinement we analyze the bulk texture of phyllosilicate-rich rocks. Here we present the results of texture analysis from a wide range of these rocks: Pleistocene poorly consolidated mud (rocks), affected only by sedimentation and burial; more highly consolidated but tectonically largely unaffected Jurassic claystone from the Opalinus Formation of the Swabian Alb; Carboniferous shales from the Harz mountains representing low-grade metamorphic and deformed rocks. Our methodical approach to quantifying the microstructural anisotropy using texture analysis in fine-grained rocks allows for the quantification of physical properties resulting from the alignment of phyllosilicates. Furthermore, it enables the prediction of direction-dependent mechanical strength, which is crucial for the establishment of long-term repositories for radioactive waste in shales and claystones.


2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.


2021 ◽  
Vol 52 (5) ◽  
pp. 1812-1825
Author(s):  
Sen Lin ◽  
Ulrika Borggren ◽  
Andreas Stark ◽  
Annika Borgenstam ◽  
Wangzhong Mu ◽  
...  

AbstractIn-situ high-energy X-ray diffraction experiments with high temporal resolution during rapid cooling (280 °C s−1) and isothermal heat treatments (at 450 °C, 500 °C, and 550 °C for 30 minutes) were performed to study austenite decomposition in two commercial high-strength low-alloy steels. The rapid phase transformations occurring in these types of steels are investigated for the first time in-situ, aiding a detailed analysis of the austenite decomposition kinetics. For the low hardenability steel with main composition Fe-0.08C-1.7Mn-0.403Si-0.303Cr in weight percent, austenite decomposition to polygonal ferrite and bainite occurs already during the initial cooling. However, for the high hardenability steel with main composition Fe-0.08C-1.79Mn-0.182Si-0.757Cr-0.094Mo in weight percent, the austenite decomposition kinetics is retarded, chiefly by the Mo addition, and therefore mainly bainitic transformation occurs during isothermal holding; the bainitic transformation rate at the isothermal holding is clearly enhanced by lowered temperature from 550 °C to 500 °C and 450 °C. During prolonged isothermal holding, carbide formation leads to decreased austenite carbon content and promotes continued bainitic ferrite formation. Moreover, at prolonged isothermal holding at higher temperatures some degenerate pearlite form.


Author(s):  
Mateus Dobecki ◽  
Alexander Poeche ◽  
Walter Reimers

AbstractDespite the ongoing success of understanding the deformation states in sheets manufactured by single-point incremental forming (SPIF), the unawareness of the spatially resolved influence of the forming mechanisms on the residual stress states of incrementally formed sheet metal parts impedes their application-optimized use. In this study, a well-founded experimental proof of the occurring forming mechanisms shear, bending and stretching is presented using spatially resolved, high-energy synchrotron x-ray diffraction-based texture analysis in transmission mode. The measuring method allows even near-surface areas to be examined without any impairment of microstructural influences due to tribological reactions. The depth-resolved texture evolution for different sets of forming parameters offers insights into the forming mechanisms acting in SPIF. Therefore, the forming mechanisms are triggered explicitly by adjusting the vertical step-down increment Δz for groove, plate and truncated cone geometries. The texture analysis reveals that the process parameters and the specimen geometries used lead to characteristic changes in the crystallites’ orientation distribution in the formed parts due to plastic deformation. These forming-induced reorientations of the crystallites could be assigned to the forming mechanisms by means of defined reference states. It was found that for groove, plate and truncated cone geometries, a decreasing magnitude of step-down increments leads to a more pronounced shear deformation, which causes an increasing work hardening especially at the tool contact area of the formed parts. Larger step-down increments, on the other hand, induce a greater bending deformation. The plastic deformation by bending leads to a complex stress field that involves alternating residual tensile stresses on the tool and residual compressive stresses on the tool-averted side incrementally formed sheets. The present study demonstrates the potential of high-energy synchrotron x-ray diffraction for the spatially resolved forming mechanism research in SPIF. Controlling the residual stress states by optimizing the process parameters necessitates knowledge of the fundamental forming mechanism action.


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