Increasing of founding properties of secondary aluminium alloys

O. V. Lyutova

doi:10.15802/stp2013/14542

Authors

O. V. Lyutova Dep. “Descriptive Geometry, Engineer and Computer Graphics”, Zaporizhzhia National Technical University, Ukraine

DOI:

https://doi.org/10.15802/stp2013/14542

Keywords:

secondary aluminum alloys, liquidity, linear shrinkage, porosity, modifier

Abstract

Purpose. To study the influence of metallurgical factors of production on casting properties of secondary aluminum alloy АК9М2. Methodology. For the experimental melts shaving amount in a charge, iron content and the quantity of modifier additive were chosen as independent variables. The components of modifier were being changed in the intervals of 25…40 % Na₂CO₃, 12…20 % SiC, 3…8 % Ti, the other – S. The microstructure of alloys was investigated under a light microscope, using the method of quantitative metallography. Influence analysis of certain parameters of alloys was conducted by mathematical statistics methods. The influence of shaving additions, iron and modifier amount on liquidity and porosity of the resulting alloys was studied. Findings. The paper shows that the increase of shaving content in the charge from 1 to 19 % and iron content in alloy from 0.66 to 2.34 % resulted in the decline of alloy liquidity on 30…35 %. Simultaneously the linear shrinkage reduction for 18…20 % and the porosity increase from 0.5 to 2.5 points were observed. The presented changes of alloy casting properties are conditioned by the amount of intermetallic phases of unfavorable form and its capacity for aeration. Increase of modifier additive from 0.02 to 0.15 % resulted in the liquidity increase on 10…15 %, the increase of linear shrinkage on 30…35 % and porosity decline from 2.5 to 0.5 points. At the same time a change of form of intermetallic phases and increase of their evenness were observed. Originality. The increase of iron concentration in silumin composition is accompanied by the decline of its liquidity. Thus, the rate of decline of alloy liquidity is proportional to the amount of dissolved iron. The character of iron influence is caused by formation of high temperature intermetallic compounds of the type Al3Fe, Al5SiFe, which promote the metal viscidity. Practical value. Practical use of the obtained scientific results would develop the technical solutions oriented to the quality indicator increase of silumin alloy.

Author Biography

O. V. Lyutova, Dep. “Descriptive Geometry, Engineer and Computer Graphics”, Zaporizhzhia National Technical University

Zhukovskiy Str., 64, 69063, Zaporizhzhia, tel. +38 (061) 769 85 32, e-mail tmzntu@gmail.com

References

Volchok I.P., Lyutova O.V. Primeneniye vtorichnykh alyuminiyevykh splavov v transportnom mashinostroyenii [Use of the secondary aluminum alloys in the transport machine building]. Visnyk Dnipropetrovskoho natsionalnoho universytetu zaliznychnoho transportu imeni akademika V. Lazariana [Bulletin of Dnipropetrovsk National University named after Academician V. Lazaryn], 2007, issue 14, pp. 225-227.

Ganina N.I., Zakharova A.M., Olenicheva V.G., Petrova L.A. Diagrammy sostoyaniya metallicheskikh sistem [Structural diagram of the metal systems], 1990, issue XXXIV, 600 p.

Liutova O., Mitiaiev O., Volchok I. Pidvyshchennia yakosti vtorynnykh aliuminiievykh splaviv [Quality improvement of the secondary aluminum alloys]. Mashynoznavstvo – Machine Science, 2007, no. 8 (122), pp. 32-35.

Mitiaiev O.A., Skuibida O.L. Pidvyshchennia yakosti aliuminiievykh splaviv metodamy rafinuvannia ta modyfikuvannia [Quality improvement of the secondary aluminum alloys by means of refinement and modification]. Visnyk Dnipropetrovskoho natsionalnoho universytetu zaliznychnoho transportu imeni akademika V. Lazariana [Bulletin of Dnipropetrovsk National University named after Academician V. Lazaryn], 2009, issue 29, pp. 195-197.

Nikitin V.I., Ivashkevich A.I., Ivlev A.V., Lesnitskiy A.N., Pron Ye.B. Modifitsirovaniye splava AK6M2 [Modification of the AK6M2 alloy]. Liteynoye proizvodstvo – Foundry engineering, 1999, no. 1, pp. 30-31.

Mondolfo L.F. Struktura i svoystva alyuminiyevykh splavov [Structure and properties of aluminum alloys]. Moscow, Metallurgiya Publ., 1979. 640 p.

Skuibida O.L., Volchok I.P. Pidvyshchennia mekhanichnykh vlastyvostei vtorynnoho syluminu AK5M2. [Mechanical properties improvement of the secondary silumin AK5M2]. Visnyk Dnipropetrovskoho natsionalnoho universytetu zaliznychnoho transportu imeni akademika V. Lazariana [Bulletin of Dnipropetrovsk National University named after Academician V. Lazaryn], 2010, issue 34, pp. 215-218.

Volchok I.P., Mitiaiev O.A. Modyfikator dlia aliuminiievykh splaviv [Modifier for aluminum alloys]. Patent UA, no. 2002108343, 2003.

Skuibida O.L., Volchok I.P. Pidvyshchennia yakosti aliuminiievykh splaviv za rakhunok modyfikuvannia [Aluminum alloys quality improvement using modification]. Visnyk Dnipropetrovskoho natsionalnoho universytetu zaliznychnoho transportu imeni akademika V. Lazariana [Bulletin of Dnipropetrovsk National University named after Academician V. Lazaryn], 2011, issue 37, pp. 235-237.

Engler S., Chen X.-G., Klinkenberg F.-J. Continuous monitoring of the degassing process in aluminum melts Cast Metals, 1995, no. 8 (1), pp. 27-34.

Koewius A. Aluminium, Automobil und Recycling einige grundsätzliche Aspekte. Automobiltechnische Zeitschrift, 1995, no. 4, pp. 248-250.

Lyutova O.V., Volchok I.P. Increase of foundry properties of secondary silumins. Archives of foundry engineering, 2008, vol. 8, pp. 89-91.

Puga. H., Barbosa J., Soares D., Silva F., Ribeiro S. Recycling of aluminum swarf by direct incorporation in aluminum melts. Journal of Materials Processing Technology, 2009, vol. 209, 5195-5203.