Search results

Filters

  • Journals
  • Autorzy
  • Słowa kluczowe
  • Data
  • Typ

Search results

Number of results: 6
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Directional solidification technique is an important research instrument to study solidification of metals and alloys. In the paper the model

[6,7,8] of directional solidification in special Artemis-3 facility was presented. The current work aimed to propose the ease and efficient

way in calibrating the facility. The introduced M coefficient allowed effective calibration and implementation of defined thermal

conditions. The specimens of AlSi alloys with Fe-rich intermetallics and especially deleterious β-Al5FeSi were processed by controlled

solidification velocity, temperature gradient and cooling rate.

Go to article

Authors and Affiliations

P. Mikołajczak
L. Ratke
Download PDF Download RIS Download Bibtex

Abstract

Iron is the most common and detrimental impurity in casting alloys and has been associated with many defects. The main consequence of

the presence or adding of iron to AlSi alloys is the formation Fe-rich intermetallics with especially deleterious β-Al5FeSi. β-Al5FeSi phases

are most often called needles on 2D micro sections, whilst platelets in 3D geometry. The x-ray tomography results have demonstrated Ferich

phases with shapes different from simple forms such as needles or platelets and presented bent and branched phases. β grown as

complicated structure of bent and branched intermetallics can decrease feeding ability, strengthen pores nucleation and eutectic colonies

nucleation leading to lower permeability of mushy zone and porosity in the castings.

Go to article

Authors and Affiliations

P. Mikołajczak
L. Ratke
Download PDF Download RIS Download Bibtex

Abstract

Solidification of AlSiFe alloys was studied using a directional solidification facility and the CALPHAD technique was applied to calculate

phase diagrams and to predict occurring phases. The specimens solidified by electromagnetic stirring showed segregation across, and the

measured chemical compositions were transferred into phase diagrams. The ternary phase diagrams presented different solidification paths

caused by segregation in each selected specimen. The property diagrams showed modification in the sequence and precipitation

temperature of the phases. It is proposed in the study to use thermodynamic calculations with Thermo-Calc which enables us to visualize

the mushy zone in directional solidification. 2D maps based on property diagrams show a mushy zone with a liquid channel in the

AlSi7Fe1.0 specimen center, where significant mass fraction (33%) of β-Al5FeSi phases may precipitate before α-Al dendrites form.

Otherwise liquid channel occurred almost empty of β in AlSi7Fe0.5 specimen and completely without β in AlSi9Fe0.2. The property

diagrams revealed also possible formation of α–Al8Fe2Si phases.

Go to article

Authors and Affiliations

P. Mikołajczak
L. Ratke
Download PDF Download RIS Download Bibtex

Abstract

Convection caused by gravity and forced flow are present during casting. The effect of forced convection generated by a rotating magnetic field on the microstructure and precipitating phases in eutectic and hypoeutectic AlSiMn alloys was studied in solidification by a low cooling rate and low temperature gradient. The chemical composition of alloys was selected to allow joint growth or independent growth of occurring α-Al, α-Al15Si2Mn4 phases and Al-Si eutectics. Electromagnetic stirring caused instead of equiaxed dendrites mainly rosettes, changed the AlSi eutectic spacing, decreased the specific surface Sv and increased secondary dendrite arm spacing λ2 of α-Al, and modified the solidification time. Forced flow caused complex modification of pre-eutectic and inter-eutectic Mn-phases (Al15Si2Mn4) depending on the alloy composition. By high Mn content, in eutectic and hypoeutectic alloys, stirring caused reduction in the number density and a decrease in the overall dimension of pre-eutectic Mn-phases. Also across cylindrical sample, specific location of occurring phases by stirring was observed. No separation effect of Mn-phases by melt flow was observed. The study provided an understanding of the forced convection effect on individual precipitates and gave insight of what modifications can occur in the microstructure of castings made of technical alloys with complex composition.
Go to article

Bibliography

[1] Mondolfo, L.F. (1976). Aluminium alloys: structure and properties. Butterworths & Co.: London, UK.
[2] Glazoff, M.V., Zolotorevsky, V.S., Belov, N.A. (2007). Casting aluminum alloys. Elsevier Science Pub Co.: Amsterdam, The Netherlands. ISBN-10:0080453708, ISBN-13:978-0080453705. https://doi.org/10.1016/B978-0-08-045370-5.X5001-9.
[3] Mikolajczak P., Ratke L. (2014). Three dimensional morphology of mn rich intermetallics in AlSi alloys investigated with X-Ray tomography. Materials Science Forum - Solidification and Gravity SolGrav VI., Miskolc. 790-791, 335-340. https://doi.org/10.4028/ www.scientific.net/MSF.790-791.335
[4] Flemings, M. (1991). Behavior of metal alloys in the semisolid state. Metallurgical. Transaction. B. 22, 269-293. https://doi.org/10.1007/BF02651227.
[5] Modigell, M., Pola, A. & Tocci, M. (2018). Rheological characterization of semi-solid metals: a review. Metals. 8(4), 245, 1-23. https://doi.org/10.3390/met8040245.
[6] Nafisi, S., Ghomashchi, R. (2016). Semi-Solid Processing of Aluminum Alloys. Springer: Berlin, Germany. ISBN: 978-3-319-40333-5, DOI: 10.1007/978-3-319-40335-9.
[7] Beil, W.L., Brollo, G.L. & Zoqui, E.J. (2021). A continuous casting device with electromagnetic stirring for production of ssm feedstock using Al-Si alloys. Materials Research. 24(3). https://doi.org/10.1590/1980-5373-MR-2020-0584.
[8] Pacheco, M.G. (2017). Electromagnetic processing of molten light alloys reinforced by micro/nanoparticles. Ph.D. Thesis, Universite Grenoble Alpes UGA, Grenoble, France, 13 March.
[9] Lazaro-Nebreda, J., Patel, J.B. & Fan, Z. (2021). Improved degassing efficiency and mechanical properties of A356 aluminum alloy castings by high shear melt conditioning (HSMC) technology. Journal of Materials Processing Technology. 294, 117146, 1-12. https://doi.org/10.1016/j.jmatprotec.2021.117146.
[10] Li, M., Murakami, Y., Matsui, I., Omura, N. & Tada, S. (2018). Imposition time dependent microstructure formation in 7150 aluminum alloy solidified by an electromagnetic stirring technique. Materials Transactions. 59(10), 1603-1609. https://doi.org/10.2320/matertrans.M2017357.
[11] Jin, C.K. (2018). Microstructure of semi-solid billets produced by electromagnetic stirring and behavior of primary particles during the indirect forming process. Metals. 8(4), 271, 1-15. https://doi.org/10.3390/met8040271.
[12] Mikolajczak, P., Janiszewski, J., Jackowski, J. (2019). Construction of the facility for aluminium alloys electromagnetic stirring during casting. In Gapiński B., Szostak M., Ivanov V. (Eds.). Advances in manufacturing II. Vol. 4. Mechanical Engineering (pp. 164-175). Cham, Switzerland, Springer. https://doi.org/10.1007/978-3-030-16943-5_15.
[13] Mikolajczak, P. (2023). Distribution and morphology of α-Al, Si and Fe-Rich phases in Al–Si–Fe alloys under an electromagnetic field. Materials. 16(9), 3304, 1-31. https://doi.org/10.3390/ma16093304.
[14] Mikolajczak, P. (2017). Microstructural evolution in AlMgSi alloys during solidification under electromagnetic stirring. Metals. 7(3), 89, 1-16. https://doi.org/10.3390/met7030089.
[15] Mikolajczak, P. (2021). Effect of rotating magnetic field on microstructure in AlCuSi alloys. Metals. 11(11), 1804, 1-23. https://doi.org/10.3390/met11111804.
[16] Mikolajczak, P., Genau, A. & Ratke, L. (2017). mushy zone morphology calculation with application of CALPHAD technique. Metals. 7(9), 363, 1-19. https://doi.org/10.3390/met7090363.
[17] Mikolajczak, P., Genau, A., Janiszewski, J. & Ratke, L. (2017). Thermo-Calc prediction of mushy zone in AlSiFeMn alloys. Metals. 7(11), 506, 1-21. https://doi.org/10.3390/met7110506.
[18] Belov, N.A., Aksenov, A.A., Eskin, D.G. (2002). iron in aluminium alloys—impurity and alloying element. 1st ed., Taylor and Francis Group: London, UK,. https://doi.org/10.1201/9781482265019.
[19] Shabestari, S.G. (2004). The effect of iron and manganese on the formation of intermetallic compounds in aluminum-silicon alloys. Materials Science and Engineering: A. 383, 289-298. https://doi.org/10.1016/j.msea.2004.06.022.
[20] Thermo-Calc 4.1—Software package from Thermo-Calc Software AB. Stockholm. Sweden. Retrieved 5 May 2023 from: www.thermocalc.se.
[21] Das, A., Ji, S. & Fan, Z. (2002). Morphological development of solidification structures under forced fluid flow: A Monte Carlo simulation. Acta Materialia. 50(18), 4571-4585. https://doi.org/10.1016/S1359-6454(02)00305-1.
[22] Li, T., Lin, X. & Huang, W. (2006). Morphological evolution during solidification under stirring. Acta Materialia. 54(18), 4815-4824. https://doi.org/10.1016/j.actamat.2006.06.013.
[23] Martinez. R.A. & Flemings, M.C. (2005). Evolution of particle morphology in semisolid processing. Metallurgical and Materials Transactins A. 36, 2205-2210. https://doi.org/10.1007/s11661-005-0339-1.
[24] Niroumand, B. & Xia, K. (2000). 3D study of the structure of primary crystals in a rheocast Al-Cu alloy. Materials Science and Engineering: A. 283(1-2), 70-75.
[25] Mendoza, R., Alkemper, J., Voorhees, P. (2003). The morphological evolution of dendritic microstructures during coarsening. Metallurgical and Materials Transactions A. 34, 481-489. https://doi.org/10.1007/s11661-003-0084-2.
[26] Kurz, W.D. Fisher, (1992). Fundamentals of Solidification. Trans Tech Public: Bäch, Switzerland, 85-90.
[27] Dantzig, J.A., Rappaz, M. (2009). Solidification. EPFL Press: Lausanne, Switzerland. ISBN 9780849382383.
[28] Stefanescu, D. (2009). Science and Engineering of Casting and Solidification. Springer: Boston, MA, USA. ISBN 978-0-387-74609-8. https://doi.org/10.1007/b135947.
[29] Wang, C.Y. & Beckermann, C. (1996). Equiaxed dendritic solidification with convection: Part II. numerical simulations for an Al-4 Wt Pct Cu Alloy. Metallurgical and Materials Transactions A. 27A, 2765-2783. https://doi.org/10.1007/BF02652370.
[30] Kattamis, T.Z., Flemings, M.C. (1965). Dendrite morphology. Microsegregation and Homogenization of low alloy steel. Transactions of the Metallurgical Society of AIME. 233(5), 992-999.
[31] Rappaz, M. & Boettinger, W. (1999). On dendritic solidification of multicomponent alloys with unequal liquid diffusion coefficients. Acta Materialia. 47(11), 3205-3219. https://doi.org/10.1016/S1359-6454(99)00188-3.
[32] Bouchard, D. & Kirkaldy, J.S. (1997). Prediction of dendrite arm spacing in unsteady- and steady-state heat flow. Metallurgical and Materials Transactions B. 28, 651-663. https://doi.org/10.1007/s11663-997-0039-x.
[33] Mortensen, A. (1991). On the rate of dendrite arm coarsening. Metallurgical Transactions A. 22, 569-574. https://doi.org/10.1007/BF02656824.
[34] Voorhees, P.W. & Glicksman, M.E. (1984). Ostwald ripening during liquid phase sintering—Effect of volume fraction on coarsening kinetics. Metallurgical Transactions A. 15, 1081-1088. https://doi.org/10.1007/BF02644701.
[35] Ferreira, A.F., Castro, J.A., Ferreira, L.O. (2017). Predicting secondary-dendrite arm spacing of the Al-4.5wt%Cu alloy during unidirectional solidification. Materials Research. 20(1), 68-75. https://doi.org/10.1590/1980-5373-MR-2015-0150.
[36] Mullis, A.M. (2003). The effects of fluid flow on the secondary arm coarsening during dendritic solidification. Journal of Materials Science. 38, 2517-2523. https://doi.org/10.1023/A:1023977723475.
[37] Steinbach, S. & Ratke, L. (2007). The influence of fluid flow on the microstructure of directionally solidified AlSi-base alloys. Metallurgical and Materials Transactions A. 38, 1388-1394. https://doi.org/10.1007/s11661-007-9162-1.
[38] Ratke, L. & Thieringer, W.K. (1985). The influence of particle motion on ostwald ripening in liquids. Acta Matallurgica. 33, 1793-1802. https://doi.org/10.1016/0001-6160(85)90003-3.
[39] Kasperovich, G., Genau, A., Ratke, L. (2011). Mushy zone coarsening in an AlCu30 alloy accelerated by a rotating magnetic field. Metallurgical and Materials Transactions A. 42, 1657-1666. https://doi.org/10.1007/s11661-010-0542-6.
[40] Diepers, H.J., Beckerman, C. & Steinbach, I. (1999). Simulation of convection and ripening in a binary alloy mush using the phase field method. Acta Materialia. 47(13), 3663-3678. https://doi.org/10.1016/S1359-6454(99)00239-6.
[41] Marsh, S.P. & Glicksman, M.E. (1996). Overview of geometric effects on coarsening of mushy zones. Metallurgical and Materials Transactions A. 27, 557-567. https://doi.org/10.1007/BF02648946.
[42] Loué, W.R. & Suéry, M. (1995). Microstructural evolution during partial remelting of AlSi7Mg alloys. Materials Science and Engineering: A. 203(1-2), 1-13. https://doi.org/10.1016/0921-5093(95)09861-5.
[43] Jackson, K.A. & Hunt, J.D. (1966). Lamellar and rod eutectic growth. Transactions of the Metallurgical Society of AIME. 236, 1129-1142.
[44] Sous, S. (2000). Instationäre Erstarrung Eutektischer Al-Si Legierungen. Ph.D. Thesis, RWTH, Aachen, Germany,
[45] Ren Z. & Junze J. (1992). Formation of a separated eutectic in Al-Si eutectic alloy. Journal of Materials Science. 27, 4663-4666. https://doi.org/10.1007/BF01166003.
[46] Mikolajczak, P. & Ratke, L. (2015). Thermodynamic assessment of mushy zone in directional solidification. Archives of foundry Engineering. 15(4), 101-109. DOI: 10.1515/afe-2015-0088.
[47] Fang, X., Shao, G., Liu, Y.Q. & Fan, Z. (2007). Effects of intensive forced melt convection on the mechanical properties of Fe containing Al-Si based alloys. Material Science and Engineering: A. 445-446, 65-72. https://doi.org/10.1016/j.msea.2006.09.038.
[48] Nafisi, S., Emad, D., Shehata, T. & Ghomashchi, R. (2006). Effects of electromagnetic stirring and superheat on the microstructural characteristics of Al-Si-Fe alloy. Materials Science and Engineering A. 432(1-2), 71-83. https://doi.org/10.1016/j.msea.2006.05.076.
[49] Steinbach, S., Euskirchen, N., Witusiewicz, V., Sturz, L. & Ratke, L. (2007). Fluid flow effects on intermetallic phases in Al-cast alloys. Transactions of Indian Institute of Metals. 60(2), 137-141.
[50] Mikolajczak, P. & Ratke, L. (2013). Effect of stirring induced by rotating magnetic field on β-Al5FeSi intermetallic phases during directional solidification in AlSi alloys. International Journal of Cast Metals Research. 26, 339-353. https://doi.org/10.1179/1743133613Y.0000000069. [51] Mikolajczak, P. & Ratke, L. (2011). Intermetallic phases and microstructure in AlSi alloys influenced by fluid flow. Supplemental Proceedings: General Paper Selections. 3, 825- 832. DOI: 10.1002/9781118062173.ch104 .

Go to article

Authors and Affiliations

P. Mikolajczak
1
ORCID: ORCID

  1. Poznan University of Technology, Poland

This page uses 'cookies'. Learn more