Hot Forging of Cast Magnesium Alloy TX31 Using Semi-Closed Die and its Finite Element Simulation

Abstract:

Magnesium alloys based on Mg-Sn-Ca system have shown improved corrosion and creep properties. In this type of alloys,Sn forms a solid solution with Mg that improves the corrosion resistance while Ca forms thermally stable intermetallic phases in the matrix enhancing the creep resistance. The Sn to Ca ratio is an important variable in deciding the type of intermetallic phases that form in the microstructure.In Mg-3Sn-1Ca alloy (TX31), a single intermetallic phase CaMgSnforms, which is responsible for its improved creep strength.With a view to evaluate its forgeability,isothermal forging experiments of TX31 were conducted on a hydraulic press in the temperature range of 350 °C to 500 °C and at speeds of 0.01 mm s^-1to 10 mm s^-1 using a semi-closed die. Finite-element (FE) simulation of the forging process was also conducted using the software DEFORM 2D to obtain the local variations of strain and strain rate. The effectivestrain values are below2.4 in the forged components and the forging loads predicted using FE simulation correlated well with the experimental data for all the forging conditions. The microstructures of the forgings show that CaMgSn phase is well distributed in the matrix which exhibited dynamically recrystallized microstructure as predicted by the processing map.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 449-454
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.449
• Online since: May 2014
• Authors: Kamineni Pitcheswara Rao*, Kalidass Suresh, Yellapregada Venkata Rama Krishna Prasad, Norbert Hort, Karl Ulrich Kainer
• Keywords: Finite Element (FE) Simulation, Forging, Magnesium Alloy, Microstructure, Plastic Behavior

References

[1] R.S. Beals, C. Tissington, X. Zhang, K.U. Kainer, J. Petrillo. M. Verbrugge, Magnesium global development: Outcomes from the TMS 2007 annual meeting, J. Metals 59 (2007) 39-42.

DOI: 10.1007/s11837-007-0102-8

[2] N. Hort, K.P. Rao, T. Abu Leil, H. Dieringa Y.V.R.K. Prasad, K.U. Kainer, Creep and hot working behavior of a new magnesium alloy Mg-3Sn-2Ca, in: M.O. Pekguleryuz, E. Nyberg, R.S. Beals, N.R. Neelameggham, (Eds. ), Magnesium Technology 2008, TMS, Warrendale PA, 2007, pp.401-406.

DOI: 10.1002/9781118359228.ch54

[3] T. Abu Leil, K.P. Rao, N. Hort, K.U. Kainer, Corrosion behavior and microstructure of a broad range of Mg-Sn-X alloys, in: A.A. Luo, N.R. Neelameggham, R.S. Beals (Eds. ), Magnesium Technology 2006, TMS, Warrendale PA, 2006, pp.281-286.

[4] T. Abu Leil, Y. Huang, H. Dieringa, N. Hort, K.U. Kainer,J. Buršík, Y. Jirásková, K. P. Rao, Effect of heat treatment on the microstructure and creep behavior ofMg-Sn-Caalloys, Mater. Sci. Forum 546-549 (2007) 69-72.

DOI: 10.4028/www.scientific.net/msf.546-549.69

[5] N. Hort, Y.D. Huang, T. Abu Leil, K.P. Rao, K.U. Kainer, Properties and processing of magnesium-tin-calcium alloys, Kovove Mater. 49 (2011) 163-177.

DOI: 10.4149/km_2011_3_163

[6] Y.V.R.K. Prasad, K.P. Rao, N. Hort, K.U. Kainer, Effect of thermal and mechanical treatments on the hot working response of Mg-3Sn-1Ca alloy, Int. J. Mater. Res. 101 (2010) 300-306.

DOI: 10.3139/146.110269

[7] Y.V.R.K. Prasad, K.P. Rao, N. Hort, K.U. Kainer, Hot working parameters and mechanisms in as-cast Mg-3Sn-1Ca alloy, Materi. Lett. 62 (2008) 4207-4209.

DOI: 10.1016/j.matlet.2008.06.035

[8] S. Kobayashi, S-I. Oh, T. Altan, Metal forming and the finite-element method, Oxford and New York: Oxford University Press. (1989).

[9] S-I. Oh, Finite element analysis of metal forming processes with arbitrarily shaped dies, Int. J. Mech. Sci. 24 (1982) 479–493.

DOI: 10.1016/0020-7403(82)90058-3

[10] A. Kozlov, M. Ohno, T. Abu Leil, N. Hort, K.U. Kainer, R. Schmid-Fetzer, Phase equilibria, thermodynamics and solidification microstructures of Mg-Sn-Ca alloys, Part 2: Prediction of phase formation in Mg-rich Mg-Sn-Ca cast alloys, Intermetallics, 16 (2008).

DOI: 10.1016/j.intermet.2007.10.011

[11] Y.V.R.K. Prasad, S. Sasidhara, Hot Working Guide: A Compendium of Processing Maps, ASM International, Materials Park OH, (1997).

[12] I. Prigogine, Time, structure, and fluctuations, Science 201 (1978) 777-787.

[13] H.J. Frost, M.F. Ashby, Deformation-Mechanism Maps: The Plasticity and Creepof Metals and Ceramics, Pergamon Press, Oxford, 1982, p.44.

[14] Y.V.R.K. Prasad, Processing maps: A status report, J. Mater. Eng. Perform. 12 (2003) 638-645.