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Kilka praktycznych wskazówek dotyczących dopuszczalnych błędów w analizach chemicznych wyrobów ze stali i stopów metali

Wyciślik Andrzej

Hutnik, Wiadomości Hutnicze

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2019

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Vol. 86, nr 5

179--181

PL

W niniejszej pracy, bazując na współpracy Politechniki Śląskiej i dawnej Huty Baildon, zestawiono dopuszczalne błędy w analizach chemicznych poszczególnych pierwiastków stopowych, oznaczanych w szerokim zakresie stężeń w wyrobach ze stali i stopów metali. Dotyczy to oznaczania, w procentach masowych: węgla od 0,005 do powyżej 0,5%, siarki od 0,003 do 0,030%, krzemu od 0,05 do 4,0%, fosforu od 0,003 do 0,045%, azotu od 0,01 do powyżej 0,25%, manganu od 0,03 do ponad 20%, niklu od 0,03 do ponad 20%, chromu od 0,10 do ponad 20%, molibdenu od 0,03 do powyżej 3,0%, wolframu od od 0,05 do powyżej 10%, glinu od 0,05 do 10,0% włącznie, tytanu i niobu 0,05% dla wszystkich zakresów stężeń.

EN

In this work, based on the cooperation of the Silesian University of Technology and the former Baildon Steelworks, permissible errors in chemical analyzes of particular alloying elements, denoted in a wide range of concentrations in steel and metal alloys, were compared. This applies to the determination in mass percentages: carbon from 0.005 to above 0.5%, sulfur from 0.003 to 0.030%, silicon from 0.05 to 4.0%, phosphorus from 0.003 to 0.045%, nitrogen from 0.01 to above 0.25%, manganese from 0.03 to over 20%, nickel from 0.03 to over 20%, chromium from 0.10 to over 20%, molybdenum from 0.03 to above 3.0%, tungsten from 0.05 to above 10%, aluminum from 0.05 to 10.0% inclusive, titanium and niobium 0.05% for all concentration ranges.

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Decomposition of the Kenticha mangano-tantalite ore by HF/H2SO4 and KOH fusion

Berhe G. G., Velázquez del Rosario A., Tadesse B., Yimam A., Woldetinsae G.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

406--414

EN

In this study, the decomposition behavior of Ta and Nb from the mangano-tantalite ore was investigated using HF/H2SO4 mixture and KOH fusion. The effects of reaction time, decomposition temperature, acid and alkaline concentrations, and particle size on the dissolution process were examined. Higher decomposition rates were achieved at 6:2 mol/dm3 ratio of HF and H2SO4, and with the addition of 10 g KOH in the alkali fusion step. In addition, similar trends in decomposition rates between two agents (HF/H2SO4 and KOH) and comparable dissolution performances were observed. The increase in the decomposition temperature initially increased the decomposition rate of mangano-tantalite for the two systems considered in this study. However, no significant change in the leaching rate of Ta and Nb was observed beyond 50 °C for the HF/H2SO4 system and above 400 °C when using the KOH fusion process. The elemental and compositional analyses of the leached residues using XRF, XRD, and FT-IR spectroscopy indicated that the acid (mixture of HF and H2SO4) decomposition resulted in slightly better dissolution performance for Ta compared with the alkaline fusion method. Overall, the results indicated that KOH can be a suitable alternative decomposition agent to the volatile, corrosive and toxic HF in the hydrometallurgical processing of tantalite ores.

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Iron Metallurgy Slags as a Potential Source of Critical Elements - Nb, Ta and REE

Kasina M., Michalik M.

Mineralogia

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2016

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Vol. 47, iss. 1/4

15--28

EN

The recovery of valuable metals from metallurgical slag disposals is a promising option to protect natural resources, limited due to technology development and increased consumption. The Ad-hoc Working Group on Defining Critical Raw Materials within the Raw Materials Supply Group has proposed a list of critical elements which have the greatest economic importance and meet the requirements of sustainable development in Europe. The goal of this study was to examine steelmaking- and blast-furnace slags from metallurgical processes to determine concentrations of elements of the greatest criticality for Poland, e.g. Nb, Ta and REE, and to discuss the viability of their recovery. Slag analyses indicate enrichment of REE relative to UCC, NASC and average chondrite compositions in blast-furnace slags and Nb and Ta in steelmaking slags. To make recovery of these critical elements reasonable and profitable, it is recommended that they be recovered together with other useful raw materials.

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The study of properties TiAl-Nb alloys

Juřica J., Losertová M., Petlák D.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2010

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z. 97

8-8

EN

Subject of this work is an intermetallic alloy based on TiAl and doped with Nb with high creep resistance and good mechanical properties. The experimental Ti-Al-Nb material with two compositions of Ti-45Al-10Nb and Ti-40Al-15Nb was prepared from master alloy TiNb (55/45 wt. %) and Al pieces by plasma melting, vacuum induction remelting and casting into the rod shape. The samples were homogenisation annealed at 1100°C for 12 hours in Ar atmosphere and water quenched from 700°C. Heat treatment at 700 °C for 8 hours in Ar atmosphere as well as in hydrogen flowing gas was realised to prepare experimental material for hydrogen effect study. Microstructure of the specimens was studied by light and scanning electron microscopies, microhardness measurement and phase microanalysis were performed. The lamellar microstructure of the samples in as-cast and heat treated conditions formed of the ? (45 at.% Al) and ?2 (41 at.% Al) phases resulted from metallographic observation and EDS phase analysis. Microhardness values of the samples decreased after annealing and quenching. Effect of hydrogen on lamellar microstructure and microhardness values was studied on the hydrogen-charged and hydrogen-free specimens. X-ray diffraction analyses were performed on Ti-Al-Nb specimens.

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Free Electron Laser in Poland

Romaniuk R. S.

Electronics and Telecommunications Quarterly

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2009

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Vol. 55, No 4

669-682

EN

The idea of building a new IVth generation of light sources of high luminosity, which use accelerators, arose in the 80ties of XXth century. Now, in a numerable synchrotron and laser laboratories in Europe, an intense applied research on free electron lasers has been carried out for a couple of years (FEL) [17,18]. Similarly, in this country, free electron laser in Poland - POLFEL [9] is in a design, a coherent light source of the IVth generation, characterized by very short pulses in the range of 10-100fs, of big power 0,2GW and UV wavelength of 27nm, of average power 1W, with effective high power third harmonic of 9nm. The laser consists of a linear superconducting accelerator 100m in length, undulator and experimental lines. It generates a monochromatic and coherent radiation and can be tuned from THz range via IR, visible to UV, and potentially to X-rays. The linac works in quasi-CW or real-CW mode. It is planned by IPJ [9,10] and XFEL-Poland Consortium [16] as a part of the ESFRI [1] priority Euro FEL infrastructure collaboration network [6], part of the European Research Area - ERA [2]. The paper discusses: FEL background in Poland as a part of EuroFEL infrastructure, FEL parameters and performance, FEL research and technical program and FEL networking in Europe and worldwide. Emphasis is put on the usage of superconducting RF TESLA technology and ties linking Polfel and the European X-Ray Free Electron Laser. The Polfel team of researchers is now dissipated worldwide among such projects as Flash and E-xfel in Desy, Cebaf in JLab, Alba in Barcelona, Elettra in Trieste, ILC in Fermilb, LCLS in SLAC. Polfel creates an unique, but quite transient chance to gather and solidly accumulate for a long time this expertise in this country again.