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1

Study of Capacitor & Diode Aging effects on Output Ripple in Voltage Regulators and Prognostic Detection of Failure

Preethi Sharma K., VijayaKumar T.

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 2

281--286

EN

Objectives: To design and simulate a buck converter and detector circuit which can prognostically indicate the power supply failure. Failure of Aluminium Electrolytic Capacitor (AEC) is considered as the parameter causing the power supply failure. To analyse variation of output ripple voltage due to possible changes in the Equivalent Series Resistance (ESR) and effective capacitance of the capacitor and design a detector to detect the failure of power supply prognostically. Methods: A DC-DC buck converter in SMPS topology is designed by assuming an input voltage of 12V with 3 volts possible fluctuations and an output voltage of 3.3 volts is desired. Simulation is carried out to measure the variation in output ripple voltage caused due to aging of electrolytic capacitor using TINA by Texas Instruments. A detector is also designed to compare the ripple voltage and a predefined threshold voltage so as to indicate the possible failure of Switched Mode Power Supply (SMPS) well in advance by monitoring the output ripple increase. Novelty: Having a fault tolerant power supply is very important in safety critical applications. Here by monitoring the output ripple variation, the degradation of AEC is predicted by calculating the ESR and capacitance variation. This simple yet effective prognostic detection will support in the design of fault tolerant power supplies. Highlight: It is found that, the ripple at the output increases with aging of the electrolytic capacitor, as with time the equivalent capacitance decreases and Equivalent Series Resistance (ESR) of the capacitor increases. The designed detector output is found to prognostically indicate the failure of SMPS.

2

Synthesis and spectroscopic interpretations of Co(II), Ni(II) and Cu(II) decxycholate complexes with molecular docking of COVId-19 protease

Refat Moamen S., Bakare Safyah B., Altalhi Tariq A., Alam Kehkashan, Al-Hazmi Ghaferah H.

Polish Journal of Chemical Technology

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2021

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Vol. 23, nr 2

54--59

EN

Co(II), Ni(II) and Cu(II) decxycholate complexes are interesting due to their biologically active and deliberate interest in the research due to their coordination properties. The microanalytical ‘elemental analysis’, molar conductivity, (infrared and Raman) spectroscopy, thermal analyses (TGA/DSC), UV-vis spectra, and ESR for copper(II) decxycholate complex investigations were performed in the structural assignments of Co(II), Ni(II) and Cu(II) decxycholate complexes. Reaction of the sodium deoxycholate ligand (C24H39O4Na) with three transition metal ions form the complexes of formulae, [M(C24H39O4)2(H2O)2] . xH2O where M = Co(II), Ni(II) and Cu(II) where x = 2 for Cu(II) and x = 4 in case of M = Co(II) or Ni(II) metal ions. The FTIR spectra of the complexes show that decxycholate molecule is present as bidentate ligand. Molecular docking utilizing to additionally examine the interaction of COVID-19 (6LU7) with different complexes of deoxycholic acid with Co(II), Ni(II) and Cu(II). Furthermore, in the case of Co(II) deoxycholate complex, the probe is surrounded by amino residues Met235, Pro241, Glu240, Pro108, Gln110, Phe294, and Ile152. The probe molecule of Ni(II) deoxycholate complex is sited close to amino acids Tyr126, Tyr239, Leu287, Leu272, and Lys137. For, Cu(II) deoxycholate complex, the residues of amino acids comprise of Pro132, Pro108, Gln110, Gly109, Ile200, Asn203, Val202, His246, Pro293 and Tyr154. The binding energy was determined from the docking reads for Co(II)–6LU7, Ni(II)–6LU7 and Cu(II)–6LU7 deoxycholate compounds were found to be −446.99, −500.52, −398.13 kcal mol−1 individually.

3

In situ methanolic solvent synthesis, spectroscopic and thermogravimetric characterizations of three new transition metal complexes of trimethoprim drug

Refat Moamen S., Al-Humaidi Jehan Y., El-Sayed Mohamed Y., Hassan Reham F.

Polish Journal of Chemical Technology

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2021

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Vol. 23, nr 1

60--67

EN

Trimethoprim drug (TMP) complexes of copper (II), cobalt (II), and nickel (II) were prepared and discussed by using elemental analysis (C, H, N analysis), magnetic, molar conductance, FTIR, Raman spectroscopy, electron spin resonance (ESR) and UV-vis spectroscopy analyses. TMP drug coordinated as a tridentate ligand towards the respected three metal ions through two nitrogen atoms of amino groups and nitrogen atom of pyrimidine ring which flanked between –NH2 groups, these assignments confirmed by spectroscopic, magnetic, ESR and thermogravimetric analyses with formulas [Cu(TMP)(H2O)3]Cl2, [Co(TMP)(H2O)3]Cl2 and [Ni(TMP) (H2O)]Cl2. Copper (II) and cobalt (II) complexes have an octahedral geometrical structure included one TMP molecule, three coordinated water molecules and two uncoordinated chlorine atoms while, nickel(II)–TMP complex has a tetrahedral geometric configuration that involved one TMP molecule, one coordinated water molecule and two uncoordinated chlorine atoms. The activation energies and other kinetic thermodynamic parameters were estimated based on the employed of the Coats-Redfern and Horowitz-Metzger equations. The nano–structured form of the synthesized TMP complexes was confirmed dependent on the transmission electron microscopy (TEM).

4

Zastosowanie katalizatora miedziowego do produkcji wodoru przez reforming parowy etanolu

Kulawska Maria, Madej-Lachowska Maria, Hamryszak Łukasz, Moroz Henryk, Wyżgoł Hildegarda

Przemysł Chemiczny

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2019

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T. 98, nr 12

1992--1995

PL

Przeprowadzono proces parowego reformingu etanolu wobec katalizatorów Cu/Al i Cu/Zr w zakresie temp. 433-573 K przy początkowym stosunku molowym etanolu do wody 1:3. Maksymalną wydajność wytwarzania wodoru uzyskano w temp. 573 K, odpowiednio 309 L/(kgkat·h) i 270 L/(kgkat·h). Dla obu katalizatorów selektywności tworzenia wodoru wynosiły ok. 22%. Produkt nie zawierał ani tlenku węgla, ani metanu. Katalizatory charakteryzowały się dobrą stabilnością.

EN

EtOH was steam-reformed over Cu/Al and Cu/Zr catalysts at 433–573 K and initial mol EtOH/H2O ratio 1:3. The H2 yields resp. 309 L/(kgcat·h) and 270 L/(kgcat·h), were achieved at 573 K (selectivity 22%). Neither MeH nor CO were detected in the reaction mixt.

5

Paramagnetic properties of Cuban red mud at low temperatures

Shvets V.

Geology, Geophysics and Environment

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2018

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Vol. 44, no. 4

373--378

EN

The electron spin resonance (ESR) spectra of Cuban red mud have been measured at three different temperatures: 295 K, 150 K and 77 K. The broad absorption line with resonance fields ∼(1.7–1.8) kOe was observed at all temperatures with values of g-factor from 3.602 to 4.020. The temperature decrease resulted in an absorption line appearance with resonance fields of 3.252 kOe (g = 2.067) at 150 K and 3.339 kOe (g = 2.086) at 77 K. The ESR-signal amplitude with resonance fields ∼(1.7–1.8) kOe decreases and the ESR-signal amplitude in the field ∼3.3 kОе increases with reduction in temperature.

6

The Influence of Natural and Model Forms of Humic Acids on the Dynamic Parameters of Model Membranes

Pisarek I., Pytel B., Filipiak A., Engel G., Olchawa R., Man D., Najwer K.

Ecological Chemistry and Engineering. S

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2016

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Vol. 23, nr 4

695--708

EN

In this paper the influence of humic acid concentrations extracted from Histosols (HA-A) and their model forms (HA-B) separated from humic substances commercially produced by Carl Roth GmbH + Co.KG on the dynamic properties of liposome membranes was determined. Differences in the quality of the humic acids (HA-A and HA-B) were determined by the 1HNMR and FTIR methods. Liposomes from the sonication of egg yolk lecithin (EYL) in an aqueous solution and synthetic Dipalmitoylphosphatidylcholine (DPPC) were used. Fluidity of liposome membranes was determined by the EPR technique with spin probes (TEMPO, 16DOIXYL). The electrical parameters of membranes were found using a Keithley 6517 electrometer. Our study showed significant differences in the influence of HA-A and HA-B on the membranes. In the bilayer membranes of the liposomes of HA-A admixture there was slightly more stiffening of the interior of the membrane in comparison to HA-B. A similar effect was observed in the surface layer of the liposome membranes. This difference is particularly evident for DPPC liposomes, however, the EYL liposomes admixture with HA-B slightly increased the fluidity of the surface layer. Electrical study confirmed this effect. The study shows that natural and model forms of humic acids differ in their effects on the activity of tested membrane models. The strong differences in the interaction of HA-A and HA-B on parameter F in DPPC liposomes can be result from the transport of humic acids connected to the metal ions inside the membranes (xenobiotics present in the environment).

7

Taurine-EVA copolymer-paraffin rods dosimeters for EPR high-dose radiation dosimetr

Maghraby A. M., Mansour A., Abdel-Fattah A. A.

Nukleonika

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2014

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Vol. 59, No. 1

9--13

EN

Taurine/EPR rods (3 × 10 mm) have been prepared by a simple technique in the laboratory where taurine powder was mixed with a molten mixture of paraffin wax and an ethylene vinyl acetate (EVA) copolymer. The binding mixture EVA/Paraffin does not present interference or noise in the EPR signal before or after irradiation. The rods show good mechanical properties for safe and multi-use handling. An EPR investigation of radiation induced radicals in taurine rods revealed that there are two types of radicals produced after exposure to gamma radiation (60Co). EPR spectra were recorded and analyzed – also the microwave power saturation and modulation amplitude were studied and optimized. Response of taurine to different radiation doses (1.5–100 kGy) was studied and found to follow a linear relationship up to 100 kGy. Radiation induced radicals in taurine persists and showed a noticeable stability over 94 days following irradiation. Uncertainities associated with the evaluation of radiation doses using taurine dosimeters were discussed and tabulated. It was found that taurine possesses good dosimetric properties using EPR spectroscopy in high doses in addition to its simple spectrum.

8

Charakterystyka stopnia ekologicznej stabilizacji rzeki

Gajda M.

Gospodarka Wodna

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2013

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Nr 9

359--360

PL

Przedstawiono propozycję wprowadzenia tzw. ekologicznej stabilizacji rzeki [ESR], poprzez wykonanie - podobnie jak kiedyś na Odrze czy Noteci - kilku niewielkich stopni piętrzących, stosując jednak zamiast jazów kozłowych gumowe bukłaki wypełnione wodą. Urządzenia takie funkcjonują od wielu lat za granicą, a od kilkunastu lat także w Polsce, m.in. na Dunajcu w Szaflarach i Waksmundzie, na Kwisie w Kliczkowie, a nawet na Wiśle w Połańcu dla potrzeb ujęcia wody do elektrowni oraz na Odrze na jazie Szczytniki. Obecnie PGE Energia Odnawialna SA montuje zamknięcie bukłakowe na jazie w Oławie.

EN

The article proposes introduction of the so-called ecological stabilisation through construction of several small damming stages, using rubber canteens filled with water instead of needle weir, as carried out on the Oder or Noteć rivers. Such facilities have been used for many years in other countries and for vr a dozen years also in Poland - for xampl on Dunajec in Szaflary and Waksmund, on Kwisa in Kliczków and even on Vistula in Połaniec, for a power generation plant water intake purposes and on Oder on the Szczytniki weir. At present, PGE Energia Odnawialna S.A. is installing canteen closure on the weir in Oława.

9

Investigation of the temporal change of the sources of Aeolian dust delivered to East Asia using electron spin resonance signals in quartz

Yamamoto Y., Toyoda S., Nagasima K., Igarashi Y., Tada R.

Geochronometria

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2013

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Vol. 40, no. 4

355--359

EN

The temporal change in the number of oxygen vacancies in quartz was investigated by observing the E1’ center in the atmospheric depositions collected at two cities in Japan in the recent past. The depositions collected at Fukuoka in March show the ESR intensities being correlated with the sum of the number of the days, in the month, on which Kosa was observed while no such correlation was found in the deposition those collected at Akita but a trend of decrease with time. The present results suggest that the number of oxygen vacancies in quartz might be useful to estimate quantitatively the contribution of the dust originated from China to the atmospheric deposition in Japan.

10

Characteristics of ESR signals and TLCLs of quartz included in various source rocks and sediments in Japan: A clue to sediment provenance

Shimada A., Takada M., Toyoda S.

Geochronometria

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2013

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Vol. 40, no. 4

334--340

EN

The variation of electron spin resonance (ESR) signal intensities and thermoluminescence colour images (TLCIs) of quartz was investigated in the present study for various rocks and sediments in Japan, to discuss the possibilities of identifying the sediment provenance. The ESR signal intensity of the E1' centre in the same grain size in granitic quartz varies from sample to sample, except for that in Quaternary samples of volcanic sediment, which is very low, close to the noise level. It was found that the diagram, ESR intensities of Al versus Ti-Li centre signal intensities, distinguish volcanic from the same grain size in granitic quartz as well as distinguish individual tephra from another. The TLCIs from volcanic quartz and some granitic quartz samples is almost red and that from the rest of granitic and metamudstone quartz is blue as results of TLCIs although the emission intensities are dif-ferent. Our results suggest that examining the multiple-centre signal intensities of ESR and the TLCIs are ef-fective to identify the source of quartz and to estimate the sediment provenance.

11

The E1' center in natural quartz: its formation and applications to dating and provenance researches

Toyoda S.

Geochronometria

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2011

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Vol. 38, no. 3

242-248

EN

Quartz is one of the minerals useful for electron spin resonance (ESR) dating. The E1' center is one of well-known paramagnetic defects in crystalline quartz. This center has a unique feature; its intensity increases on heating. An electronic process to explain this increase was found to be con-trolled not only by the number of oxygen vacancies, which are the precursors, but also by the number of Al hole centers, which depend on the previous radiation dose and on the Al concentration. The maximum intensity on heating is called the heat treated E1' center, which has been posited to correspond to the number of oxygen vacancies in quartz and was found to be correlated with the ages of the host granites (Toyoda and Hattori, 2000). The experimental results on spin-spin relaxation times of the E1' center indicate that external beta and gamma rays create oxygen vacancies in natural quartz rather than alpha or alpha recoil particles (Toyoda et al., 2005). The correlation between the numbers of the oxygen vacancies in quartz and the ages of the host granite made it possible to distinguish the quartz of a sedimentary reservoir from another with different age of crystallization (Toyoda and Naruse, 2002). Quartz fractions extracted from leoss and atmospheric deposition in Japan and from sediments in Japan sea were analyzed by ESR. The temporal change of the contributions from two dust sources in China were discussed in the context of climate change.

12

The grain size influence on the E1'centre observed in quartz of atmospheric deposition at two Japanese cities : a preliminary study

Yamamoto Y., Toyoda S., Nagasima K., Igarashi Y., Tada R.

Geochronometria

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2010

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Vol. 37

9-12

EN

The grain size influence on the number of oxygen vacancies in quartz was investigated by ESR in atmospheric deposition collected at two Japanese cities, Fukuoka and Akita, in 1969 and 1971. The finer grain size fraction shows the highest value of concentration of oxygen vacancies, most closely resembling dust originating in the Taklamakan desert. Month to month and year to year variation of the dependence was also observed which could possibly be attributed to the variation of the mixture ratio of at least two dust sources in China, A conclusive statement can not be made at this stage.

13

ESR dating of marine barite in chimneys deposited from hydrothermal vents

Okumura T., Toyoda S., Sato F., Uchida A., Ishibashi J., Nakai S.

Geochronometria

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2010

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Vol. 37

57-61

EN

Electron Spin Resonance (ESR) dating of marine barite in chimneys deposited from hydrothermal vents was attempted to determine the time since hydrothermal activity occurred. In this study, we used Barite (BaSO4) precipitated in icroenvironments in the chimneys deposited from the hydrothermal vents at the Archaean site in South Mariana spreading centre (12°56.4'N, 143°37.9'E) and at Hakurei site in the Izena caldron (27°15‘N, 127°04‘E) for ESR measurements. ESR spectrum of marine barite is characterized by an electron-type centre with g values of 2.0034, 2.0022 and 1.9995 attributed to SO3 –. The signal intensity increased with gamma ray dose. The dose rates of hydrothermal chimneys from the Archaean site and from the Hakurei site were calculated using a model that assumed a grain size and that incorporation of radionuclides after 226Ra in U series into the chimney, and assuming the efficiency of the defect formation by alpha particles to be the same as that for OSL. The ESR ages were estimated to be 470 years old for barite from the Archaean site and 5670 years old for one from the Hakurei site, although there is a considerable difference between the present ESR ages and the 210Pb/226Ra disequilibrium ages previously reported.

14

Optical studies of undoped GaP grown by LEC method

Surma B., Wnuk A., Piersa M., Strzelecka S., Pawłowski M., Jurkiewicz-Wegner E.

Materiały Elektroniczne

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2009

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T. 37, nr 2

38-46

EN

The features of undoped LEC GaP crystals with particular emphasis on their luminescence properties are presented. Hall and GDMS measurements revealed that C and Si are the main residual shallow impurities. Semi-insulating features of the samples were controlled by the presence of the phosphorous anti-site defect, P4PGa. Its presence was confirmed by ESR measurements as well as the emission at 1.05 eV. For p-type samples with phosphorous antisite defect, P4PGa, and high carbon concentration an emission at 1.9 eV has been observed. We tentatively assign this emission to the recombination of the excitons bound with isoelectronic complex PGaCp. A deep-centre luminescence with the maximum at 1.33 eV was dominant in n-type GaP and in electron-irradiated samples. The obtained results indicate that this emission results from native defect complex.

PL

W pracy przedstawione są badania niedomieszkowanych kryształów GaP otrzymywanych w ITME metodą LEC ze szczególnym uwzględnieniem ich własności luminescencyjnych. Pomiary Halla, absorpcyjne i GDMS wykazały, że głównymi płytkimi domieszkami resztkowymi w otrzymywanych kryształach są węgiel i krzem. Półizolujące własności badanych kryształów determinowane były obecnością fosforowego antystrukturalnego defektu P4PGa. Obecność jego została potwierdzona poprzez obecność linii rezonansowej w widmie ESR, jak również poprzez obecność emisji w podczerwieni z maksimum przy l .05 eV. W kryształach typu p, w których potwierdzona została obecność defektu P4PGa oraz stwierdzono relatywnie wysoką koncentrację węgla w widmie luminescencyjnym pojawiło się pasmo luminescencyjne z maksimum przy l .9 eV. Nasza sugestia odnośnie pochodzenia tej emisji wiązana jest z wytworzeniem się isoelektronowego kompleksu PGaCp. W niedomieszkowanych próbkach typu w jak również w próbce naświetlanej elektronami luminescencja pochodząca od głębokich centrów zdominowana była obecnością pasma leżącego przy 1.33 eV. Przeprowadzone badania wykazały, że jest ona związana z obecnością kompleksu wytworzonego przez macierzyste atomy sieci, natomiast nie zależy od koncentracji domieszek resztkowych.

15

Vibrational spectra, electronic excited states and magnetic properties of the copper(II) ions in alkylaminoacetylurea complexes

Ciurla H., Hanuza J., Talik Z., Korabik M., Mrozinski J.

Materials Science Poland

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2009

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Vol. 27, No. 1

5--21

EN

Copper(II) complexes with alkylaminoacetylurea ligands were synthesized and studied by means of IR, Raman, electron absorption and luminescence spectroscopies, as well as by ESR and magnetic methods. The spectroscopic and magnetic studies were performed in the 4-300 K and 1.9-300 K temperature ranges, respectively. The Cu2+ ions in these complexes are four coordinated having distorted squareplanar surroundings. The dependence of the spectroscopic parameters on the alkyl radical of the ligand is discussed. At low temperatures, very weak ferromagnetic interactions are observed for the C3 and C5 alkyls, and an antiferromagnetic one is observed for the remaining complexes, with C4 and C6-C18 alkyls.

16

Design and Analysis of Supercapacitors Energy Storage System for Energy Stabilization of Distribution Network

Sahay K., Dwivedi B.

Electrical Power Quality and Utilisation. Journal

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2009

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Vol. 15, iss. 1

25--32

EN

Supercapacitors are the devices which can be store significant amounts of energy and quickly release it, their main application is for short term power compensation application where they can release a large amount of energy quickly and then can he recharged with smaller current. In this paper the use of Supercapacitors bank is explored for energy stabilisation and maintaining the voltage profile of the distribution system at the load point. The proposed supercapacitor bank is designed to improve the voltage profile of a distribution system by supplying the energy in case of demand and recharging the Supercapacitors bank in valley period. The designed bank is of 50 k\Vh{180 MJ) of energy, 440 V voltages and peak power of 30 kVV capacities for supply of energy in case of instantaneous need. The result shows that the SCESS can supply the instantaneous power for the back up the loads even though the voltage may drop up to 100 V; this SCESS can back up the load from 1.60-9.9974 hours depending upon the power demand while maintaining the minimum discharge voltage ratio and availability of useful energy.

17

Analysis of experimental results obtained by ESR and VAR process for special steels

Zaman F., Iorga G., Ionescu M., Petrescu A., Carciumareasa D.

Archives of Metallurgy and Materials

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2008

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Vol. 53, iss. 2

629-632

EN

The paper presents the results regarding quality of special steels for aero industry, obtained by two different processes: Electro Slag Remelting (ESR) and Vacuum Arc Remelting (VAR) on pilot experiments. The main object of these trials was obtaining super clean steels (oxygen <20 ppm, hydrogen <1 ppm, nitrogen <20 ppm, sulphur <50 ppm, phosphorus <100 ppm) and a controlled solidificated structure of steel semis. The experiments took off the benefits of vacuum arc remelting process, for decreasing gaseous content of steels versus electro slag remelting process which can improve the decreasing of sulphur content of steel. In order to analyse the influence of a double vacuum process VIM – VAR (Vacuum Induction Melting and Vacuum Arc Remelting) on quality of steel, some trials were also performed.

PL

Artykuł przedstawia wyniki dotyczące jakości stali specjalnych stosowanych w przemyśle lotniczym, uzyskane z dwóch różnych procesów: elektrożużlowego przetapiania stali i przetapiania w próżni na podstawie badań pilotażowych. Głównym przedmiotem badań było uzyskanie super czystych stali (tlen <20 ppm, wodór <1 ppm, azot <20 ppm, siarka <50 ppm, fosfor <100 ppm) i kontrola struktury bliźniaków w krzepnącej stali. W doświadczeniach wykorzystano korzyści płynące z odgazowania stali w procesie próżniowym, naprzeciw możliwościom elektrożużlowego przetapiania, które poprawia odsiarczanie stali. Wykonane zostało również kilka prób, aby przeanalizować wpływ procesu VIM – VAR na jakość stali.

18

Cost reduction of TiAl by alternative production and integration of TiAl scrap recycling - concepts and vacuum-metallurgical equipment

Lochbichler C., Friedrich B., Jarczyk G., Scholz H.

Advances in Materials Science

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2008

|

Vol. 8, nr 1(15)

67-74

EN

Due to high corrosion resistance and low density titanium alum in ides show a great potential as material for structural applications in the aerospace and automotive industry. However the high actual production costs for semi-finished products slow down a break through to mass production of TiAl. Current research projects at IME, Aachen funded by AIF "Otto von Guericke" and BMBF aim on cost reduced production methods of TiAl and on the minimisation of downgrading TiAl scrap. This article presents firstly the state of the art of TiAl production by vacuum arc (re)melting (V AR) or induction skull melting (ISM). A comparison of new process routes under special consideration of recycling issues will follow. Innovative processing and equipment concepts are shown by intelligent combination of well known vacuum melting and remelting processes such as vacuum induction melting, specialized using ceramic lining and deoxidisation with e.g. electro slag remelting (ESR). For each process step and accordingly equipment the metallurgical opportunities are pointed out and the way to make use of them within the process route is described. Requirements on input material and final metal quality addicted to the processing route and refining techniques with their adjustment in respect to TiAl are mentioned. Selected results of laboratory and pilot scale experiments done at IME in Aachen and equipment needs therefore are shown.

19

Cost reduction of TiAl by alternative production and integration of TiAl scrap recycling - concepts and vacuum-metallurgical equipment

Lochbichler C., Friedrich B., Jarczyk G., Scholz H.

Advances in Materials Science

|

2007

|

Vol. 7, nr 4(14)

81-88

EN

Due to high corrosion resistance and low density titanium aluminides show a great potential as material for structural applications in the aerospace and automotive industry. However the high actual production costs for semi-finished products slow down a break through to mass production of TiAl. Current research projects at IME, Aachen funded by AIF "Otto von Guericke" and BMBF aim on cost reduced production methods of TiAl and on the minimisation of downgrading TiAl scrap. This article presents firstly the state of the art of TiAl production by vacuum arc (re)melting (VAR) or induction skull melting (ISM). A comparison of new process routes under special consideration of recycling issues will follow. Innovative processing and equipment concepts are shown by intelligent combination of well known vacuum melting and remelting processes such as vacuum induction melting, specialized using ceramic lining and deoxidisation with e.g. electro slag re-melting (ESR). For each process step and accordingly equipment the metallurgical opportunities are pointed out and the way to make use of them within the process route is described. Requirements on input material and final metal quality addicted to the processing route and refining techniques with their adjustment in respect to TiAl are mentioned. Selected results of laboratory and pilot scale experiments done at IME in Aachen and equipment needs therefore are shown.

20

Filtrowanie stali stopowych w próżni jako alternatywna technologia elektrożużlowego przetapiania

Pogorzałek J., Galisz U., Bulkowski L., Marcisz J.

Prace Instytutu Metalurgii Żelaza

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2006

|

T. 58, nr 3

34-40

PL

Użytkownicy wyrobów stalowych wymagają często do określonych zastosowań tzw. stali "czystych" (o bardzo małej ilości i wielkości wtrąceń niemetalicznych). Jednym ze sposobów wyprodukowania "czystej" stali jest technologia elektrożużlowego przetapiania (EŻP). Na przestrzeni lat intensywnie rozwijała się też technologia wytapiania czystych stali w próżniowym piecu indukcyjnym (PPI) oraz technologia filtrowania stali przez filtry ceramiczne, w której następuje głębokie oczyszczenie stali z wtrąceń niemetalicznych. W IMŻ przeprowadzono próby połączenia technologii PPI z filtracją stali w warunkach obniżonego ciśnienia uzyskując stal o porównywalnej jakości do stali po EŻP.

EN

The users of steel products often require so-called pure steels (with a very small amount and size of non-metallic inclusions) for specific applications. One of the methods for making "pure" steel is the electroslag remelting technology (ESR). Over the years, there was also developing the technology for melting steel in the vacuum induction furnace (PPI) and technology for filtering steel through ceramic filters in which deep steel purification of non-metallic inclusions takes place. In the Institute for Ferrous Metallurgy, the attempts to combine PPI technology and steel filtration under the reduced pressure conditions were made. The result was obtaining the steel of quality comparable to the quality of steel after ESR.