Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 97
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

In this study, the spatial variation of daily and monthly concentration precipitation index and its aggressive-ness were used in 23 rainfall stations in the extreme north-east of Algeria over the period 1970–2010. The trend was analysed by the Mann–Kendall (MK) test. The results show that daily precipitation concentration index (CI) values are noticeably higher in places where the amount of total precipitation is low, the results of MK test show that areas of high precipitation concentration tend to increase. The seasonality and aggressiveness of precipita-tion are high in the eastern and western parts of the study region (eastern and central coastal of Constantine catchments), whereas a moderately seasonal distribution with low aggressiveness is found in the middle of the study area (plains and central Seybouse catchment). As a result, the modified Fournier index (MFI) has a signifi-cant correlation with annual precipitation, whereas the CI and monthly precipitation concentration index (PCI) show an opposite correlation in relation to annual precipitation.
Go to article

Authors and Affiliations

Hanane Bessaklia
Abderrahmane Nekkache Ghenim
Abdessalam Megnounif
Javier Martin-Vide
Download PDF Download RIS Download Bibtex

Abstract

A trial to determine the atmospheric precipitants and their role as the element of pollutants budget in transport of pollutants into water ecosystems has been presented. Total dawnfall method were used with sedimentary funnels of 0.28 m2 . The pH, conductivity, ammonia, nitrites, nitrates, organic nitrogen, phosphates, organic carbon, chlorides, sulphates, calcium, magnesium and heavy metals (iron, zinc, lead and cadmium) were determined. The analysis results are similar to the results obtained at other sample points of Upper Silesia. The range of pollutant concentration changes indicate the objective factors for the analysis results dispersion. With the method apllied, only average values of concentration can be used for the evaluation of the chemical status of downfall waters and atmospheric air. The atmospheric precipitants thought underestimated are siginificant source for pollutants (nitrogen, phosphorus and heavy metals) introduced directly to the trophogenical zone of water ecosystem. In the case of the Kłodnica hydro-junction reservoirs, the loads of nitrogen and phosphorus from atmospheric precipitations are determined as "dangerous surface loading". The presence of considerable loads of magnesium in the precipitations indicates the possibility of chemical precipitation of polyphosphates from epilimnion zone, and are consequence the quicker transportation of phosphorus to the bottom sediments. It can activate the intra-reservoir enrichment process.
Go to article

Authors and Affiliations

Maciej Kostecki
Download PDF Download RIS Download Bibtex

Abstract

Among the elements that compose steel slags and blast furnace slags, metallic precipitates occur alongside the dominant glass and crystalline phases. Their main component is metallic iron, the content of which varies from about 90% to 99% in steel slags, while in blast furnace slags the presence of precipitates was identified with the proportion of metallic iron amounting to 100%. During observations using scanning electron microscopy and X-ray spectral microanalysis it has been found that the form of occurrence of metallic precipitates is varied. There were fine drops of metal among them, surrounded by glass, larger, single precipitates in a regular, spherical shape, and metallic aggregates filling the open spaces between the crystalline phases. Tests carried out for: slags resulting from the open-hearth process, slags that are a by-product of smelting in electric arc furnaces, blast furnace slags and waste resulting from the production of ductile cast iron showed that depending on the type of slag, the proportion and form of metallic precipitates is variable and the amount of Fe in the precipitates is also varied. Research shows that in terms of quality, steel and blast furnace slag can be a potential source of iron recovery. However, further quantitative analyses are required regarding the percentage of precipitates in the composition of slags in order to determine the viability of iron recovery. This paper is the first part of a series of publications aimed at understanding the functional properties of steel and blast furnace slags in the aspect of their destructive impact on the components of devices involved in the process of their processing, which is a significant operational problem.

Go to article

Authors and Affiliations

Andrzej Norbert Wieczorek
Iwona Jonczy
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

Height, frequency and spatial differentiation of atmospheric precipitation of the summer season for the period 1975-1982 are presented. Results of the respective investigations are compared with atmospheric precipitation in other areas of the western coast of Spitsbergen.

Go to article

Authors and Affiliations

Kazimierz Marciniak
Rajmund Przybylak
Download PDF Download RIS Download Bibtex

Abstract

The paper presents the research results of the influence of the precipitation hardening on hardness and microstructure of selected Al-Si and Al-Cu alloys obtained as 30 mm ingots in a horizontal continuous casting process. The ingots were heat treated in process of precipitation hardening i.e. supersaturation with subsequent accelerated or natural ageing. Moreover in the range of the study it has been carried out investigations of chemical constitution, microscopic metallographic with use of scanning electron microscope with EDS analysis system, and hardness measurements using the Brinell method. On basis of obtained results it has been concluded that the chemical constitution of the investigated alloys enables to classify them into Al alloys for the plastic deformation as EN AW-AlSi2Mn (alternatively cast alloy EN AC-AlSi2MgTi) and as EN AW-AlCu4MgSi (alternatively cast alloy EN AC-AlCu4MgTi) grades. Moreover in result of applied precipitation hardening has resulted in the precipitation from a supersaturated solid solution of dispersive particles of secondary phases rich in alloying element i.e. Si and Cu respectively. In consequence it has been obtained increase in hardness in case of AlSi2Mn alloy by approximately 30% and in case of AlCu4MgSi alloy by approximately 20% in comparison to the as-cast state of continuous ingots.
Go to article

Authors and Affiliations

T. Wróbel
P.M. Nuckowski
P. Jurczyk
Download PDF Download RIS Download Bibtex

Abstract

The high mechanical properties of the Al-Li-X alloys contribute to their increasingly broad application in aeronautics, as an alternative forthe aluminium alloys, which have been used so far. The aluminium-lithium alloys have a lower specific gravity, a higher nucleation andcrack spread resistance, a higher Young’s module and they characterize in a high crack resistance at lower temperatures. The aim of theresearch planned in this work was to design an aluminium alloy with a content of lithium and other alloy elements. The research includedthe creation of a laboratorial melt, the microstructure analysis with the use of light microscopy, the application of X-ray methods to identify the phases existing in the alloy, and the microhardness test.
Go to article

Authors and Affiliations

J. Augustyn-Pieniążek
S. Rzadkosz
H. Adrian
M. Choroszyński
Download PDF Download RIS Download Bibtex

Abstract

This paper presents the results of the research aiming at determining content of selected anions in the samples containing precipitated water (rainwater and snowfall water) by isotachophoretic method. This work is a continuation of the complex pollution monitoring in the areas of Siedlce and Olecko (near Suwałki). The samples were collected from November 2006 to May 2007. Days of sampling depended on atmospheric conditions. Sulfate and hydrogen carbonate turned up to be the dominant anions in samples which were collected in city centers. Higher contents were observed in Siedlce. The content of nitrites in both cities was low. The highest concentration of sulfates and chlorides in rainwater was obtained in the samples collected near the Company of Thermal Energy (CTE) in Siedlce. Similar results of sulfate concentration were observed in Olecko. In samples of snowfall water (collected near to the CTE) sulfates and sulfites were the dominating anions.
Go to article

Authors and Affiliations

Ireneusz Chrząścik
Magdalena Szymalska
Mariusz Kluska
Download PDF Download RIS Download Bibtex

Abstract

The phase transformation dynamic and electrical conductivity equations of the aged Cu-2.7Ti-2.5Ni-0.8V alloy were established in this work. The microstructure evolution and precipitated phases were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The mechanical properties were tested using a hardness testing machine and universal test machine, and the electrical conductivity was measured by the eddy conductivity gauge. The results show that NiTi intermetallic compounds are formed during the solidification, and these phases such as Ni3Ti and NiV3 are precipitated after aging treatment. The fracture morphology displays that a large number of shallow and equiaxed dimples occur on the tensile fracture, indicating a typical ductile fracture. After aging treatment at 450°C for 240 min, the hardness, tensile strength, elongation and electrical conductivity of the Cu-2.7Ti-2.5Ni-0.8V alloy are 184 HV, 459 MPa, 6.3% and 28.72% IACS, respectively.
Go to article

Authors and Affiliations

Jia Liu
1 2
ORCID: ORCID
Jituo Liu
3
ORCID: ORCID
Xianhui Wang
3
ORCID: ORCID

  1. Xi’an Polytechnic University, School of Materials Science and Engineering, Xi’an 710048, P.R. China
  2. Xi’an University of Technology, School of Mechanical and Precision Instrument Engineering, Xi’an 710048, P. R. China
  3. Xi’an University of Technology, School of Materials Science and Engineering, Xi’an 710048, P. R. China
Download PDF Download RIS Download Bibtex

Abstract

Lysimeters represent the ideal tool for direct measurement of soil water balance components in soil profiles. Changes in the water content in a soil monolith can be measured with sufficient accuracy by the precise lysimeter weighing system.Water content changes in soil monolith as derived from lysimeter mass represent one of the basic water balance compo-nent. This paper deals with the development and comparison of individual soil water balance components in two different soil profiles from the Easter-Slovakian-Lowland. Two lysimeter vessels were filled monolithically with two different soil profiles covered with grass: one sandy soil profile from locality Poľany and one silty-loam soil profile from locality Vysoká nad Uhom. A constant groundwater level of 1 m below ground level was maintained in both soil profiles. Under the same meteorological conditions, all differences in the development of water balance components were caused only by the differences in soil profiles. The actual evapotranspiration and water flows at the bottom of the soil profiles were compared. Sandy soils are generally considered to be more prone to drought than silty-loam soils. Under the specific conditions of this experiment (maintaining a constant groundwater level) the opposite was shown, when the silty-loam soil profile was more prone to drought than sandy soil profile. Sandy soilprofile from Poľany reacted more quickly to precipitation (or evaporation). Due to the higher hydraulic conductivity of the sandy soil compared to the silty-loamy soil, the groundwater level response to external stimuli was much faster.

Go to article

Authors and Affiliations

Andrej Tall
Dana Pavelková
Download PDF Download RIS Download Bibtex

Abstract

Identification and ecological diagnostics of the influence of basic load parameters (the cumulative effect of air temperature, the amount of precipitation) is a fundamental aspect of the wastewater sludge treatment at drying beds. The positive dynamics of atmospheric precipitation and the long-term functioning of natural and technical systems for wastewater sludge treatment under the influence of excessive atmospheric moisture does not allow the treatment/drying of precipitation, which provokes soil pollution with subsequent diffusion of pollutants into groundwater, which leads to the degradation of the natural environment components interacting with drying beds. The article is devoted to the adaptation of the process of treatment/drying of wastewater sludge at drying beds. The method includes identification of the dynamics of climatic factors of a long-term chronological series, which makes it possible to predict the effect of atmospheric precipitation on the wastewater sludge drying. The costs for the implementation and subsequent use of the proposed method are absent or insignificant (in the conditions of an increase in usable area during the modernisation of existing drying beds) in comparison with the costs of well-known and widespread methods of deliquefaction.
Go to article

Bibliography

ALBERTSON O., BURRIS B., REED S., SEMON J., SMITH J. JR., WALLACE A. 1987. Design manual: dewatering municipal wastewater sludges [online]. EPA/625/1-87/014 (NTIS PB95186417). [Access 15.10.2021]. Available at: https://cfpub.epa.gov/si/si_public_re-cord_Report.cfm?Lab=NRMRL&dirEntryID=46573
CASAJUS N., PÉRIÉ C., LOGAN T., LAMBERT M.C., DE BLOIS S., BERTEAUX D. 2016. An objective approach to select climate scenarios when projecting species distribution under climate change. PLoS One. Vol. 11(3). DOI 10.1371/journal.pone.0152495e0152495.
DAMERT M., BAUMGARTNER R.J. 2017. Intra-sectoral differences in climate change strategies: evidence from the global automotive industry. Business Strategy and Environment. Vol. 27(3) p. 265– 281. DOI 10.1002/bse.1968.
DREGULO A.M. 2019. Identifikatsiya i prognozirovaniye klimaticheskoy nagruzki dlya proyektirovaniya i ekspluatatsii ilovykh kart (ploshchadok) [Identification and prediction of climatic loads for design and operation of drying beds]. Voda i ekologiya: problemy i resheniya. No. 1(77) p. 35–43. DOI 10.23968/2305-3488.2019.24.1.35-43.
DREGULO A.M. 2020. Vliyaniye klimaticheskikh faktorov na eksplua-tatsiyu prirodno-tekhnicheskikh sistem obrabotki otkhodov vodootvedeniya [Influence of climatic factors on the operation of natural and technical systems for waste treatment of waste-water disposal]. Vestnik Moskovskogo Unviersiteta. Seriya Geografiya. No. 6 p. 32–40.
DREGULO A.M., BOBYLEV N.G. 2021a. Integrated assessment of ground-water pollution from the landfill of sewage sludge. Journal of Ecological Engineering. Vol. 22(1) p. 68–75. DOI 10.12911/22998993/128872.
DREGULO A., BOBYLEV N. 2021b. Heavy metals and arsenic soil contamination resulting from wastewater sludge urban landfill disposal. Polish Journal of Environmental Studies. Vol. 30(1) p. 81–89. DOI 10.15244/pjoes/121989.
DREGULO A.M., RODIONOV V.Z. 2020. «Goryachiye tochki» KHELKOM: zhivotnovodcheskiy kompleks «Pashskiy» kak ob”yekt nakoplen-nogo vreda okruzhayushchey srede [HELCOM “hot spots”: cattle-breeding complex “Pashskiy” as the object of accumulated environmental damage]. Theoretical and Applied Ecology. No. 4 p. 49–54. DOI 10.25750/1995-4301-2020-4-049-054.
DREGULO A.M., VITKOVSKAYA R.F. 2018. Microbiological evaluation of soils of sites with accumulated ecological damage (sewage dumps). Fiber Chemistry. Vol. 50(3) p. 243–247. DOI 10.1007/s10692-018-9969-0.
DREGULO A.M., VITKOVSKAYA R.F. 2020. Analysis of foreign and domestic practice of operating sludge platforms to minimize negative environmental impact. IOP Conference Series: Earth and Environmental Science. Vol. 613, 012026. DOI 10.1088/1755-1315/613/1/012026.
DROZDOV O.A. 1954. O svoystvakh integral’no-raznostnykh krivykh [On the properties of integral-difference curves]. Trudy Gosu-darstvennoy geofizicheskoy observatorii. Vyp. 162. Leningrad p. 3–6.
EL-GENDY A.S., EL-KASSAS H.I., RAZEK T.M.A., ABDEL-LATIF H. 2017. Phyto-dewatering of sewage sludge using Panicum repens L. Water Science and Technology. Vol. 75(7) p. 1667–1674. DOI 10.2166/wst.2017.039.
EVILEVICH A.Z. 1957. K raschetu ilovykh ploshchadok [To the calculation of sludge-drying beds]. Vodosnabzheniye i sanitar-naya tekhnika. No. 10 p. 30–32.
HAANDEN A., LUBBE J. 2007. Biological waste water treatment – Design and optimisation of activated sludge system. Leidschendam. Quist Publishing. ISBN 9781780407753 pp. 360.
JAWECKI B., PAWĘSKA K., SOBOTA M. 2017. Operating household wastewater treatment plants in the light of binding quality standards for wastewater discharged to water bodies or to soil. Journal of Water and Land Development. No. 32 (I–III) p. 31–39. DOI 10.1515/jwld-2017-0004.
KATTSOV V.M. (ed.) 2017. Doklad o klimaticheskikh riskakh na territorii Rossiyskoy Federatsii [Report on climate risks in the Russian Federation]. Saint-Petersburg. Glavnaya geofizicheskaya observatoriya im. A. I. Voyeykova. ISBN 978-9500833-1-5 pp. 105.
NIELSEN S., STEFANAKIS A.I. 2020. Sustainable dewatering of industrial sludges in sludge treatment reed beds: Experiences from pilot and full-scale studies under different climates. Applied Sciences. Vol. 10(21), 7446. DOI 10.3390/app10217446.
PANDEY M.K., JENSSEN P.D. 2015. Reed beds for sludge dewatering and stabilization. Journal of Environmental Protection. Vol. 06(04) p. 341–350. DOI 10.4236/jep.2015.64034.
Rosgidromet 2016. Doklad ob osobennostyakh klimata na territorii Rossiyskoy Federatsii za 2018 god [A report on climate features on the territory of The Russian Federation in 2018]. Moskva. Federal’naya sluzhba po gidrometeorologii i monitoringu okru-zhayushchey sredy. ISBN 978-5-906099-58-7 pp. 70 [online]. [Access 10.10.2020]. Available at: http://www.meteorf.ru/upload/pdf_download/%D0%94%D0%BE%D0%BA%D0%BB%D0%B0% D0%B42016.pdf
Rosgidromet 2019. Doklad ob osobennostyakh klimata na territorii Rossiyskoy Federatsii za 2018 god [A report on climate features on the territory of The Russian Federation in 2018]. Moskva. Federal’naya sluzhba po gidrometeorologii i monitoringu okru-zhayushchey sredy. ISBN 978-5-906099-58-7 pp. 79.
ROSER-RENOUF C., MAIBACH E.W., LI J. 2016. Adapting to the changing climate: An assessment of local health department preparations for climate change-related health threats 2008–2012. PloS ONE. Vol. 11(3). DOI 10.1371/journal.pone.0151558.
SP 32.13330.2012. Kanalizatsiya. Naruzhnyye seti i sooruzheniya. Aktualizirovannaya redaktsiya SNiP 2.04.03-85 [Sewerage. Out-door networks and structures. Updated version of SNiP 2.04.03- 85] [online]. [Access 10.10.2020]. Available at: http://docs.cntd.ru/document/1200094155
VORONOV Y.V., YAKOVLEV S.V. 2006. Vodootvedeniye i ochistka stochnykh vod. Uchebnoye izdaniye [Water disposal and waste-water treatment. Textbook for universities]. Moskva. Izdatel’stvo ASV. ISBN 5-93093-119-4 pp. 677.
ZOLINA O.G., BULYGINA O.N. 2016. Sovremennaya klimaticheskaya izmenchivost’ kharakteristik ekstremal’nykh osadkov v Rossii [Current climatic variability of extreme precipitation in Russia]. Fundamental’naya i prikladnaya klimatologiya. No. 1 p. 84–103. DOI 10.21513/2410-8758-2016-1-84-103.
Go to article

Authors and Affiliations

Andrei Mikhailovich Dregulo
1 2
ORCID: ORCID

  1. National Research University “Higher School of Economics”, Pechatnikov str. 16, 198099 Saint-Petersburg, Russia
  2. Saint-Petersburg Federal Research Center of the Russian Academy of Sciences (SPC RAS), Scientific Research Centre for Ecological Safety of the Russian Academy of Sciences, Korpusnaya str. 18, 197110, Saint-Petersburg, Russia
Download PDF Download RIS Download Bibtex

Abstract

The purpose of the work was to determine the morphology of graphite that occurs in vermicular cast iron, both in the as-cast state and after heat treatment including austenitization (held at a temperature of 890 °C or 960 °C for 90 or 150 min) and isothermal quenching (i.e. austempering, at a temperature of 290 °C or 390 °C for 90 or 150 min). In this case, the aim here was to investigate whether the heat treatment performed, in addition to the undisputed influence of the cast iron matrix on the formation of austenite and ferrite, also affects the morphology of the vermicular graphite precipitates and to what extent. The investigations were carried out for the specimens cut from test coupons cast in the shape of an inverted U letter (type IIb according to the applicable standard); they were taken from the 25mm thick walls of their test parts. The morphology of graphite precipitates in cast iron was investigated using a Metaplan 2 metallographic microscope and a Quantimet 570 Color image analyzer. The shape factor F was calculated as the quotient of the area of given graphite precipitation and the square of its perimeter. The degree of vermicularization of graphite was determined as the ratio of the sum of the graphite surface and precipitates with F <0.05 to the total area occupied by all the precipitations of the graphite surface. The examinations performed revealed that all the heat-treated samples made of vermicular graphite exhibited the lower degree of vermicularization of the graphite compared to the corresponding samples in the as-cast state (the structure contains a greater fraction of the nodular or nearly nodular precipitates). Heat treatment also caused a reduction in the average size of graphite precipitates, which was about 225μm2 for the as-cast state, and dropped to approximately 170-200 μm2 after the austenitization and austempering processes.
Go to article

Bibliography

[1] Sorelmetal, On the nodular cast iron. (2006). Warsaw: Ed. Metals & Minerals Ltd.
[2] Tupaj, M., Orłowicz, A. W., Mróz, M., Kupiec, B., et al. (2020). Ultrasonic Testing of Vermicular Cast Iron Microstructure. Archives of Foundry Engineering. 20(4), 36-40. DOI: 10.24425/afe.2020.133345.
[3] Guzik, E. & Kleingartner, T. (2009). A study on the structure and mechanical properties of vermicular cast iron with pearlitic-ferritic matrix. Archives of Foundry Engineering. 9(3), 55-60.
[4] Zhang, M.X., Pang, J.C., Qiu, Y., Li, S.X., et al. (2020). Influence of microstructure on the thermo-mechanical fatigue behavior and life of vermicular graphite cast irons. Materials Science & Engineering A. 771, 138617.DOI: 10.1016/J.MSEA.2019.138617.
[5] Zhang, Y., Guo, E., Wang, L., Zhao, S., et al. (2020). Effect of the matrix structure on vermicular graphite cast iron properties. International Journal of Materials Research. 111(5), 379-384. DOI: 10.3139/146.111891.
[6] Qiaoqin, G., Zhong, Y., Ding, G., Dong, T. et al. (2019). Research on the oxidation mechanism of vermicular graphite cast iron. Materials. 12, 3130; DOI: 10.3390/ma12193130.
[7] Perzyk, M., Waszkiewicz, S., Kaczorowski, M., Jopkiewicz, A. (2000). Foundry. Warsaw: ED. Science and Technology.
[8] Kosowski, A. (2008). Foundations of foundry. Krakow: Ed. Scientific Akapit.
[9] Soiński, M.S. & Warchala, T. (2006). Cast iron moulds for glassmaking industry. Archives of Foundry. 6(19), 289-294.
[10] Warchala, T. (1988). Metallurgy and iron founding. Part 1 The structure and properties of cast iron. Ed. Częstochowa University of Technology.
[11] Andrsova, Z., Volesky, L. (2012). The potential of isothermally hardened iron with vermicular graphite. Comat 2021. Recent trends in structural materials. 21 - 22. 11. 2012, Plzeň, Czech Republic, EU.
[12] Gumienny, G. & Kacprzyk, B. (2018). Copper in Ausferritic Compacted Graphite Iron. Archives of Foundry Engineering. 18(1), 162-166. DOI: 10.24425/118831.
[13] Pytel, A., Gazda, A. (2014) Evaluation of selected properties in austempered vermicular cast iron (AVCI). Transactions of Foundry Research Institute. LIV(4), 23-31. DOI: 10.7356/iod.2014.18.
[14] Andršová, Z., Kejzlar, P., Švec, M. & Skrbek, B. (2017). The effect of heat treatment on the structure and mechanical properties of austempered iron with vermicular graphite. Materials Science Forum. 891, 242-248. DOI: 10.4028/www.scientific.net/MSF.891.242.
[15] Kazazi, A., Montazeri, S.M. & Boutorabi, S.M.A. (2020). The austempering kinetics, microstructural development, and processing window in the austempered, Fe-3.2C-4.8Al compacted graphite cast iron. Iranian Journal of Materials Science and Engineering. 17(4), 46-54. DOI: 10.22068/ijmse.17.4.46.
[16] Jakubus, A., Kostrzewa, J., Ociepa, E. (2021). The influence of parameters of heat treatment on the microstructure and strength properties of the ADI and the AVGI irons. METAL 2021, 30th Anniversary International Conference on Metallurgy and Materials. May 26 - 28, 2021, Brno, Czech Republic, EU (pp.34-39). DOI: 10.37904/metal.2021.4082.
[17] Podrzucki, C. (1991). Cast iron. Structure, properties, applications. vol. 1 and 2, Cracow: Ed. ZG STOP. (in Polish).
[18] Soiński, M.S. & Mierzwa, P. (2011). Effectiveness of cast iron vermicularization including ‘conditioning’ of the alloy. Archives of Foundry Engineering. 11(2), 133-138.
[19] Warchala, T. (1995). Metallurgy and iron founding. Part 2 Cast iron technology. Ed. Czestochowa University of Technology.
[20] Mierzwa, P. & Soiński, M.S. (2010). The effect of thermal treatment on the mechanical properties of vermicular cast iron. Archives of Foundry Engineering. 10(spec.1), 99-102.
[21] Mierzwa, P., Soiński, M.S. (2012). Austempered cast iron with vermicular graphite. 70th World Foundry Congress (WFC 2012): Monterrey, Mexico, April 2012, (pp. 25-27).
[22] Mierzwa, P. & Soiński, M.S. (2014). Austempered cast iron with vermicular graphite. Foundry Trade Journal International. 188(3713), April 2014, 96-98.
[23] Polish Standard PN-EN 1563, Founding. Spheroidal graphite cast iron, (2000).
[24] Soiński, M.S. (1980). Application of shape measurement of graphite precipitates in cast iron in optimising the spheroidizing process. Acta Stereologica. 5(2), 311-317.
Go to article

Authors and Affiliations

M.S. Soiński
1
A. Jakubus
1
ORCID: ORCID
B. Borowiecki
1
P. Mierzwa
2

  1. The Jacob of Paradies University in Gorzów Wielkopolski, ul. Teatralna 25, 66-400 Gorzów Wielkopolski, Poland
  2. Czestochowa University of Technology, Poland
Download PDF Download RIS Download Bibtex

Abstract

The study presents methods to be used for improving the performance parameters of car engine pistons made of EN AC-AlSi12CuNiMg alloy according to the PN-EN 1706: 2011. Pistons of slow sucking and turbocharged engines were researched. A solution heat and ageing treatments were applied according to four variants. Temperatures of the solution heat treatment were: 550 ±5°C; 510°C ±5°C; and alternate: 276 ±5°C/510 ±5°C. The solution time ranged from 6 min to 4 h. Temperatures of the ageing heat treatment were 20°C and 250°C, while the ageing time ranged from 1,5 to 3h. Natural ageing was performed in 5 days. Measurements of hardness HRB and the piston diameters were performed. An improvement in the performance parameters of combustion engines was observed. Three solution heat treatment and ageing variants, allowed to obtain the pistons with hardness equal/higher than pistons of the turbocharged engines. The test results confirmed the possibility of providing a piston with properties exceeding the high load parameters specified by the manufacturer. Further studies will make it possible to improve the effects of the proposed solutions.
Go to article

Bibliography

[1] Stone, R. (2012). Introduction to Internal Combustion Engines. Fourth Edition, SAE and Macmillan.
[2] Heywood, J.B. (2018). Internal Combustion Engines Fundamentals, Second Edition, McGraw-Hill Education.
[3] Kirkpatrick, A.T. (2020). Internal Combustion Engines: Applied Thermosciences. Fourth Edition, John Wiley & Sons.
[4] Bosch, R. (2018). Automotive Handbook. 10th Edition: Robert Bosch GmbH
[5] Siemińska-Jankowska, B. & Pietrowski, S. (2003). The effects of temperature on strength of the new piston aluminum materials. Journal of KONES Internal Combustion Engines. 10(1-2), 237-250.
[6] Wajand, A., Wajand, J. (2005). Reciprocating internal combustion engines. Wydawnictwa Naukowo Techniczne PWN. (in Polish).
[7] Manasijevic, S., Pavlovic-Acimovic, Z., Raic, K., Radisa, R. & Kvrgi´c, V. (2013). Optimisation of cast pistons made of Al–Si piston alloy. International Journal of Cast Metals Research. 26(5), 255-261.
[8] Javidani, M. & Larouche, D. (2014). Application of cast Al–Si alloys in internal combustion engine components. International Materials Reviews. 59(3), 132-158.
[9] Pietrowski, S. (2001) Silumins. Łódź: Wydawnictwo Politechniki Łódzkiej. (in Polish).
[10] Poniewierski, Z. (1989). Crystallization, Structure and Mechanical Properties of Silumins. Warszawa: WNT. (in Polish).
[11] Kaufman, J.G., Rooy, E.L. (2004). Aluminum Alloy Castings: Properties, Processes and Applications. ASM International.
[12] Zolotorevsky, V.S., Belov, N.A., Glazoff, M.V. (2007). Casting Aluminium Alloys. Elsevier: Oxford, UK, pp. 327-376.
[13] Pezda, J. (2015). The effect of the T6 head treatment on change of mechanical properties of the AlSi12CuNiMg alloy modified with strontium. Archives of Metallurgy and Materials. 60(2), 627-632.
[14] Czekaj, E., Fajkiel, A. & Gazda, A. (2005). Short-lived ultrahigh temperature silicon spheroidization treatment of silumins. Archiwum Odlewnictwa. 5(17), 51-68. (in Polish).
[15] Dobrzański, L.A., Reimann, L. & Krawczyk, G. (2008). Influence of the ageing on mechanical properties of the aluminium alloy AlSi9Mg. Archives of Materials Science and Engineering. 31, 37-40.
[16] Pezda, J. (2010). Heat treatment of EN AC-AlSi13Cu2Fe silumin and its effect on change of hardness of the alloy. Archives of Foundry Engineering. 10(1), 131-134.
[17] Pezda, J. (2014). Effect of a selected heat treatment parameters on technological quality of a silumin-cast machinery components; Bielsko-Biała: ATH Scientific Publishing House: Bielsko-Biała, Poland.
[18] Pezda, J. & Jarco, A. (2016). Effect of T6 heat treatment parameters on technological quality of the AlSi7Mg alloy. Archives of Foundry Engineering. 16(4), 95-100.
[19] Czekaj, E., Kwak, Z., Garbacz-Klempka, A. (2017). Comparison of impact of immersed and micro-jet cooling during quenching on microstructure and mechanical properties of hypoeutectic silumin AlSi7Mg0.3. Metallurgy and Foundry Engineering. 43(3), 153-168.
[20] Pezda, J. & Jezierski, J. (2020). Non-standard T6 heat treatment of the casting of the combustion engine cylinder head. Materials. 13(18), 4114.
[21] Jarco, A. & Pezda, J. (2021). Effect of heat treatment process and optimization of its parameters on mechanical properties and microstructure of the AlSi11(Fe) alloy. Materials (Basel) 14(9), 2391.
[22] Nikitin, K.V., Chikova, O.A., Amosov, E.A. & Nikitin, V.I. (2016). Shortening the time of heat treatment of silumins of the Al – Si – Cu system by modifying their structure. Metal Science and Heat Treatment. 58(7), 400-404.
[23] Prudnikov, A., Prudnikov, V. (2019). The mode of hardening heat treatment for deformable piston hypereutectic silumins. International Scientific Journal Materials science. Non-equilibrium phase transformations. 5(3), 74-77.
[24] Kantoríková, E., Kuriš, M. & Pastirčák, R. (2021). Heat treatment of AlSi7Mg0.3 Aluminium alloys with increased zirconium and titanium content. Archives of Foundry Engineering. 21(2), 89-93.
[25] Kuriš, M., Bolibruchova, D. M., Matejka M. & Kantoríková, E. (2021). Effect of the precipitation hardening on the structure of AlSi7Mg0.3Cu0.5 alloy with addition of Zr and combination of Zr and Ti. Archives of Foundry Engineering. 21(1), 95-100.
[26] Rychter, T., Teodorczyk, A. (2006). Theory of piston engines. Wydawnictwa Komunikacji i Łączności. (in Polish).

Go to article

Authors and Affiliations

M. Trepczyńska-Łent
1
ORCID: ORCID
K. Műller
2

  1. Mechanical Engineering Faculty, Bydgoszcz University of Science and Technology, Al. prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland
  2. Bergerat Monnoyeur Sp. z o.o. – Caterpillar, Poland
Download PDF Download RIS Download Bibtex

Abstract

The microalloying elements such as Nb, V are added to control the microstructure and mechanical properties of microalloyed (HSLA) steels. High chemical affinity of these elements for interstitials (N, C) results in precipitation of binary compound, nitrides and carbides and products of their mutual solubility – carbonitrides. The chemical composition of austenite, as well as the content and geometric parameters of undissolved precipitates inhibiting the growth of austenite grains is important for predicting the microstructure, and thus the mechanical properties of the material. Proper selection of the chemical composition of the steel makes it possible to achieve the required properties of the steel at the lowest possible manufacturing cost. The developed numerical model of carbonitrides precipitation process was used to simulate and predict the mechanical properties of HSLA steels. The effect of Nb and V content to change the yield strength of these steels was described. Some comparison with literature was done.
Go to article

Bibliography

[1] Adrian H. (2011). Numerical modeling of heat treatment processes. AGH Kraków. (in Polish).
[2] European Committee for Standardization (2019). Hot Rolled Products of Structural Steels: Technical Delivery Conditions for Flat Products of High Yield Strength Structural Steels in the Quenched and Tempered Condition
[3] Jan, F., Jaka, B. & Grega, K. (2021). Grain size evolution and mechanical properties of Nb, V–Nb, and Ti–Nb boron type S1100QL steels. Metals. 11(3), 492. https://doi.org/10.3390/met11030492.
[4] Gladman, T. (1997). The physical metallurgy of microalloyed steels institute of materials. vol. 363. London, UK. Search in. [5] Blicharski, M. (2004). Materials engineering: steel. WNT: Warszawa. (in Polish).
[6] Marynowski, P., Adrian, H. & Głowacki, M. (2019) Modeling of the kinetics of carbonitride precipitation process in high-strength low-alloy steels using cellular automata method. Journal of Materials Engineering and Performance. 28(7), 4018-4025. https://doi.org/10.1007/s11665-019-04170-4.
[7] Marynowski, P., Adrian, H. & Głowacki, M. (2018). Cellular Automata model of carbonitrides precipitation process in steels. Computer Methods in Materials Science. 18(4), 120-128. ISSN 1641-8581.
[8] Marynowski, P., Adrian, H. & Głowacki, M. (2013). Cellular automata model of precipitation in microalloyed niobium steels. Computer Methods in Materials Science. 13(4), 452-459. ISSN 1641-8581.
[9] Adrian, H. (1992). Thermodynamic model for precipitation of carbonitrides in high strength low alloy steels containing up to three microalloying elements with or without additions of aluminum. Materials Science and Technology. 8, 406-420. https://doi.org/10.1179/mst.1992.8.5.406.
[10] Adrian, H. (1995). Thermodynamic model of carbonitride precipitation in low-alloy steels with increased strength with application to hardenability tests. Kraków: AGH. (in Polish).
[11] Adrian, H. (1995). Thermodynamic calculations of carbonitride precipitation as a guide for alloy design of microalloyed steels. In Proceedings of the International Conference Microalloying'95, 11-14 June 1995(285-307). Pittsburgh.
[12] Adrian, H. (1999). A mechanism for the effect of vanadium on the hardenability of medium carbon manganese steel. Materials Science and Technology. 15, 366-378. https://doi.org/10.1179/026708399101505987.
[13] Cuddy, L.J. & Raley, J.C. (1987). Austenite grain coarsening in microalloyed steels. Metallurgical Transactions A. 14, 1989-1995. https://doi.org/10.1007/BF02662366.
[14] Cuddy, L.J. (1984). The effect of micro alloy concentration on the recrystallization of austenite during hot deformation. Processing of Microalloyed Austenite (Pittsburgh) TMS-AIME Warrendale PA.
[15] Goldschmidt, H.J. (1967). Interstitial Alloys. Butterworth-Heinermann.
[16] Lifschitz, I.M. & Slyozov, V.V. (1961). The kinetics of precipitation from supersaturated solid solution. Journal of Physics and Chemistry of Solids. 19(1/2), 35-50. https://doi.org/10.1016/0022-3697(61)90054-3.
[17] Zając, S., Siwecki, T. & Hutchinson, W.B. (1998). Lagneborg R. The role of carbon in enhancing precipitation strengthening of V-microalloyed steels. Material Science Forum. 284, 295-302. https://doi.org/10.4028/www.scientific.net/MSF.284-286.295.
[18] Langberg, R., Hutchinson, W.B., Siwecki, T. & Zając, T. (2014). The role of vanadium in microalloyed steels. Sweden: Swerea KIMAB
Go to article

Authors and Affiliations

Przemysław Marynowski
1
ORCID: ORCID
Marcin Hojny
1
Tomasz Dębiński
1
ORCID: ORCID

  1. AGH University of Krakow, Poland
Download PDF Download RIS Download Bibtex

Abstract

In this paper results of microstructural observations for series of CuZn39Pb2 alloys produced from qualified scraps are presented. The individual alloy melts were differentiated in terms of thermal parameters of continuous casting as well as refining methods and modifications. Structural observations performed by SEM and TEM revealed formation of different types of intermetallic phases including “hard particles”. EDS results show that “hard particles” are enrich in silicon, phosphorus, iron, chromium and nickel elements. Additionally, formation of Al-Fe-Si and Al-Cr in alloy melts was observed as well. It was found that quantity and morphology of intermetallic phases strongly depends upon the chemical composition of raw materials, process parameters, modifiers and refining procedure applied during casting. It was observed that refining process results in very effective refinement of intermetallic phases, whereas modifiers, particularly carbon-based, results in formation of large particles in the microstructure.

Go to article

Authors and Affiliations

A.W. Bydałek
A. Kula
L. Błaż
K. Najman
Download PDF Download RIS Download Bibtex

Abstract

The paper presents the results of microstructural and mechanical investigation of long-term aged TP347HFG austenitic stainless steel. Ageing was performed at a time of up to 30 000 hours and the temperature of 600 and 650◦C. Ageing was proved to lead to the precipitation of secondary phase particles not only inside grains but also on the boundaries of grains and twins. The MX precipitates were observed inside the grains. However, M23C6 carbides and sigma phase precipitates were observed on grain boundaries. The changes in the microstructure of the examined steel translated into the mechanical properties, i.e. initially observed growth and then the decrease of yield strength and a gradual decrease in impact energy. The overageing process – a decrease in strength properties – was associated with the growth of the size of M23C6 carbides and the precipitation of the sigma phase. The reduction of impact energy in TP347HFG austenitic stainless steel was found to be associated with the precipitation of M23C6 carbides in the case of the 600◦C temperature, and the M23C6 carbides and sigma phase in the case of the 650◦C temperature. The rate of changes in the microstructure and mechanical properties depended on the ageing temperature.
Go to article

Authors and Affiliations

Grzegorz Golański
1
ORCID: ORCID
Hanna Purzyńska
2

  1. Czestochowa University of Technology, Department of Materials Science, Armii Krajowej 19, 42-200 Częstochowa, Poland
  2. Łukasiewicz Research Network – Institute for Ferrous Metallurgy, K. Miarki 12-14, 44-100 Gliwice, Poland
Download PDF Download RIS Download Bibtex

Abstract

Certain chemical parameters such pH, specific electric conductivity (SpC) and concentrations of chloride ions (Cl-) have been analysed in samples of precipitation collected close to the Polish Polar Station at Hornsund (PPS), SW Spitsbergen. On the basis of seasonal data from years 1993-1994 and 1998-1999, some differences are apparent from the two sets. There is also a marked difference in the seasonal results, especially with respects to pH values; summer precipitation (pH of which can be as low as 3.78) is much more acidic than winter. This was particularly notable in respect of the summer of 1993, and was presumably the result of a relatively unusual atmospheric circulation and a high influx of airborne contaminants from Europe. The wide variation in specific electrical conductivity measurements is considered to be related to variations in wind direction and speed. That precipitation the highest total dissolved salts, of 11.7 mm w.e. (water equivalent), (November 1993), provided 10.7 g of salt per square metre of tundra near the Polish Polar Station. The proximity of the sea, consequently the development of marine aerosols, largely determines the chemical nature of the precipitation. Thus, variations in the chloride ion concentrations during the study periods more or less reflect the variations in the marine aerosol influences on the nature of the polluted precipitation. An analysis of the atmospheric circulation reveals that the most acid precipitation occurs most frequently in the C-8 type of circulation (cyclonic S + SW) and also, less so, for type C-3 (anticyclonic S + SW).

Go to article

Authors and Affiliations

Maciej Burzyk
Jerzy Burzyk
Piotr Głowacki
Download PDF Download RIS Download Bibtex

Abstract

Independent Arctic records of temperature and precipitation from the same proxy archives are rare. Nevertheless, they are important for providing detailed information on long-term climate changes and temperature-precipitation relationships in the context of large-scale atmospheric dynamics. Here, we used chironomid and cladoceran fossil assemblages to reconstruct summer air- temperature and water-level changes, during the past 400 years, in a small lake located in Finnish Lapland. Temperatures remained persistently cold over the Little Ice Age (LIA), but increased in the 20th century. After a cooler phase in the 1970s, the climate rapidly warmed to the record-high temperatures of the most recent decades. The lake-level reconstruction suggested persistently wet conditions for the LIA, followed by a dry period between ~1910 and 1970 CE, when the lake apparently became almost dry. Since the 1980s, the lake level has returned to a similar position as during the LIA. The temperature development was consistent with earlier records, but a significant local feature was found in the lake-level reconstruction – the LIA appears to have been continuously wet, without the generally depicted dry phase during the 18th and 19th centuries. Therefore, the results suggest local precipitation patterns and enforce the concept of spatially divergent LIA conditions.

Go to article

Authors and Affiliations

Tomi P. Luoto
E. Henriikka Kivilä
Bartosz Kotrys
Mateusz Płóciennik
Marttiina V. Rantala
Liisa Nevalainen
Download PDF Download RIS Download Bibtex

Abstract

Magnetite nanoparticles have become a promising material for scientific research. Among numerous technologies of their synthesis, co-precipitation seems to be the most convenient, less time-consuming and cheap method which produces fine and pure iron oxide particles applicable to environmental issues. The aim of the work was to investigate how the co-precipitation synthesis parameters, such as temperature and base volume, influence the magnetite nanoparticles ability to separate heavy metal ions. The synthesis were conducted at nine combinations of different ammonia volumes - 8 cm3, 10 cm3, 15 cm3 and temperatures - 30°C, 60°C, 90°C for each ammonia volume. Iron oxides synthesized at each combination were examined as an adsorbent of seven heavy metals: Cr(VI), Pb(II), Cr(III), Cu(II), Zn(II), Ni(II) and Cd(II). The representative sample of magnetite was characterized using XRD, SEM and BET methods. It was observed that more effective sorbent for majority of ions was produced at 30°C using 10 cm3 of ammonia. The characterization of the sample produced at these reaction conditions indicate that pure magnetite with an average crystallite size of 23.2 nm was obtained (XRD), the nanosized crystallites in the sample were agglomerated (SEM) and the specific surface area of the aggregates was estimated to be 55.64 m2·g-1 (BET). The general conclusion of the work is the evidence that magnetite nanoparticles have the ability to adsorb heavy metal ions from the aqueous solutions. The effectiveness of the process depends on many factors such as kind of heavy metal ion or the synthesis parameters of the sorbent.

Go to article

Authors and Affiliations

Magdalena Bobik
Irena Korus
Lidia Dudek

This page uses 'cookies'. Learn more