Alüminyum Alaşımının Derin Çekilmesine Sıcaklığın Etkisinin Deneysel ve Sayısal Olarak Araştırılması

Öz

5000 serisi Al-Mg alaşımları, süneklik, iyi kaynak edilebilirlik, yüksek mukavemet ve düşük ağırlık özelliklerinden dolayı geniş bir uygulama alanına sahiptirler. Bununla birlikte bu alaşımların oda sıcaklığında şekillendirilmesi mikroyapılarından dolayı çelik saclara nazaran zordur. Bu problemlerin üstesinden gelmenin en etkili yolu ılık şekillendirmedir. Bu çalışmada, şekillendirme sıcaklığının limit çekme oranı, ıstampa kuvveti, et kalınlığı, mikrosertlik ve gerilmeye etkisi deneysel ve sayısal olarak araştırılmıştır. Deneyler 25^oC, 100^oC, 175^oC ve 250^oC sıcaklıklarında, 3600 N baskı plakası kuvvetinde gerçekleştirilmiştir. Yapılan çalışmalar sonucunda sıcaklığın artması ile et kalınlığı değişiminin daha homojen hale geldiği, limit çekme oranının arttığı, mikrosertlik, gerilme ve ıstampa kuvvetinin azaldığı belirlenmiştir. Sonlu elemanlar yöntemi (SEY) ile elde edilen sayısal sonuçların deneysel veriler ile elde edilen sonuçlara yakın oldukları gözlenmiştir. 

Anahtar Kelimeler

• AA5754 sac malzeme,limit çekme oranı,ılık derin çekme,mikrosertlik,sonlu elemanlar yöntemi

Experimental and Numerical Investigation of the Effect of Temperature on Deep Drawing of Aluminum Alloy

Öz

5000 series of Al-Mg alloys have found very wide application areas due to their ductility, good weldability, high strength and low weight properties. However, forming of these alloys is more difficult than steel sheets at room temperature due to their microstructure. The most effective way to overcome these problems is the warm forming. In this study, the effect of forming temperature on limit drawing ratio, punch force, wall thickness, microhardness and stress of cup were investigated experimentally and numerically. The experiments were conducted at 25°C, 100°C, 175°C, and 250°C temperatures under 3600 N blank holder force.  As a result of the studies, it was determined that an increase in forming temperature led to more homogeneous distribution of wall thickness, increase of limit drawing ratio, decrease of microhardness, stress and punch forces. The finite element analysis (FEA) model results were also in a good agreement with the experimental results. 

Anahtar Kelimeler

• AA5754 sheet metal,limit drawing ration,warm deep drawing,microhardness,finite element analysis

Kaynakça

1. [1] Seçgin O. and Savaş V.,. “An experimental investigation of forming load and side-wall thickness obtained by a new deep drawing die”, Int J. Mater Form, 3:209–213, (2010).
2. [2] Özek C. and Ünal E., “The effect of die/blank holder angles on limit drawing ratio and wall thickness in deep drawing of square cups”, Journal of the Faculty of Engineering and Architecture of Gazi University, Vol 27, No 3, 615-622, (2012).
3. [3] Greene D.L. and DiCicco, J.,. “Engineering-economic analyses of automotive fuel economy potential in the United States”. ORNL/TM-2000/26, Oak Ridge National Laboratory, Oak Ridge, TN, (2000).
4. [4] Panicker S.S., Singh H.G., Panda S. K. and Dashwood R., “Characterization of tensile properties, limiting strains, and deep drawing behavior of AA5754-H22 sheet at elevated temperature”, Journal of Materials Engineering and Performance, 24:4267–4282, (2015).
5. [5] Abedrabbo N., Pourboghrat F. and Carsley J., “Forming of AA5182-O and AA5754-O at elevated temperatures using coupled thermo-mechanical finite element models”, International Journal of Plasticity 23:841–875, (2007).
6. [6] Laurent H., Coër J., Manach P.Y., Oliveira M.C. and Menezes L.F., “Experimental and numerical studies on the warm deep drawing of an Al–Mg alloy”, International Journal of Mechanical Sciences, 93: 59–72, (2015).
7. [7] Özturk F., Pekel H. ve Halkacı H.S., “The effect of strain-rate sensitivity on formability of AA 5754-O at cold and warm temperatures”, Journal of Materials Engineering and Performance, 20: 77–81, (2011).
8. [8] Halim H., Wilkinson D.S. and Niewczas M., “The Portvein-Le Chatelier(PLC) effect and shear band formation in an AA5754 alloy”, Acta Mater., 55: 4151–4160, (2007).

9. [9] Laurent H., Coër J., Grèze R., Manach, P.Y., Andrade-Campos A., Oliveira M.C. and Menezes L.F., “Mechanical behaviour and springback study of an aluminium alloy in warm forming conditions”, International Scholarly Research Network ISRN Mechanical Engineering, ID:381615, (2011).
10. [10] Tebbe P.A. and Kridli G.T., “Warm forming of aluminium alloys: an overview and future directions,” International Journal of Materials and Product Technology, 21(1-3): 24–40, (2004).
11. [11] Laurent H., Grèze R., Manach P.Y. and Thuillier S., “Influence of constitutive model in springback prediction using the split-ring test,” International Journal of Mechanical Sciences, 51(3): 233–245, (2009).
12. [12] Toros S., Ozturk F. and Kacar I., “Review of warm forming of aluminum-magnesium alloys”, Journal of Materials Processing Technology, 207: 1–12, (2008).
13. [13] Ren L.M., Zhang S.H., Palumbo G., Sorgente D. and Tricarico L., “Numerical simulation on warm deep drawing of magnesium alloy AZ31 sheets”, Materials Science and Engineering A, 499: 40–44, (2009).
14. [14] Erdin M.E., Aykul H. and Tunalıoğlu Ş., “Forming of high strength/low formability metal sheets at elevated temperatures”, Mathematical and Computational Applications, 10(3): 331-340, (2005).
15. [15] Kotkunde N., Deole A.D., Gupta A.K., Singh S.K., “Comparative study of constitutive modeling for Ti-6Al-4V alloy at low strain rates and elevated temperatures”, Materials and Design, 55: 999–1005, (2014).
16. [16] Samantaray D., Mandal S. and Bhaduri A.K., “A comparative study on Johnson Cook, modified Zerilli–Armstrong and Arrhenius-type constitutive models to predict elevated temperature flow behaviour in modified 9Cr–1Mo steel”, Comput Mater Sci, 47, 568–576, (2009).
17. [17] Dutton T., Mohamed M. and Lin J., “Simulation of warm forming of aluminium AA5754 for automotive panels”, 12th International LS-DYNA User Conference, (2012).
18. [18] Abedrabbo N., Pourboghrat F. and Carsley J., “Forming of aluminum alloys at elevated temperatures - Part 2: Numerical modeling and experimental verification”, Int. J. Plast., 22: 342-373, (2006).
19. [19] van den Boogaard A., “Thermally enhanced forming of aluminum sheet modeling and experiments”, Ph.D. thesis, Twente University, (2002).
20. [20] Bolt P.J, Lamboo N.A.P.M. qnd Rozier P.J.C.M., “Feasibility of warm drawing of aluminum products”, J Mater Proc Technol, 115(1): 118–21, (2001).
21. [21] Taşdemir V., “Açılı derin çekme kalıplarında sıcaklığın limit çekme oranına etkisinin araştırılması”, Doktora tezi, Fırat Ünv. Fen Bilimleri Enstitüsü, (2016).
22. [22] Cotterell M., Schambergerova J. and Ziegelheim J., “Dependence of micro-hardness on deformation of deep-drawing steel sheets”, Journal of Materials Processing Technology, 124(3): 293–296, (2002).