PROTEC-12068:No.of Pages 12 ARTICLE IN PRESS JOURNAL OF MATERIALS PROCESSING TECHNOLOGY XXX (2008)XXX-XX) /15073 four digit system.Themajor al USA 2x1 hat c Manganese fo 20253035 uused series for 9XXx are main alloving elements. use ong Fig.1-Av nun application of the aluminum and its alloys this Khare 2000:sch warz et al,2001). use or .For expanding use ofalu u Aluminum alloys are effective materials for the reduction s in many areas of vehicle weight and are expanding their applications.Fig. o overcome.The formability of the aluminum alloys at ratesthe usage of a on to and A emperatures is generally lower than at both cryogenic has recently increased their aluminum alloy usage. xpect that m alloys usage in Japan A alloys especially 5xXX series alloys and is related to the cle production holds steady at around 10 million units.the due o ng.wh at ele ve age around () ing at crvogenic temperatur nging th at high ot forr Ihe dema num a uch as creep mechanisms which m eformation and cavitations at grain boundaries which may nduce premature the by casting such as engines.wheels.exhaust decor how Aluminum for pass nge vehicles ightweight vehicles have become a key targ get for car mar including bumper beams ou and in forgings including suspension parts Fig 2. 5 g the vehicle nerforma the most e comfort and r abil s that minun ty (Cole and S erman, 1995).Aluminum will prob 2kg of stee can lead to a net reduction me ve the ns in the utomotiv industry (Carle ents on co emissions a shown coa emission is uts in arious allo elements n area can also have a big influence on the sustainabilit of a ca ome of the important sign aspects of a ca t and T ates the material has big infl car eight un (300.000km).although i would about 30%mo 0201202020302094·2003 de while incr asing the employment in the short term (Fuhrmann,1979). Miller et al.,2000;Turkish Statistical Institute,2004). s.S.et al..Review of warm forming of aluminum-magnesium alloys.I.Mater.Process.Tech.(2008Please cite this article in press as: Toros, S., et al., Review of warm forming of aluminum–magnesium alloys, J. Mater. Process. Tech. (2008), doi:10.1016/j.jmatprotec.2008.03.057 PROTEC-12068; No. of Pages 12 ARTICLE IN PRESS 2 journal of materials processing technology xxx (2008) xxx–xxx it very attractive for fabricating various aircraft and missile parts. The present system utilized to identify aluminum alloys is the four digit designation system. The major alloy element for each type is indicated by the first digit, i.e., 1XXX indicates aluminum of 99.00% minimum; 2XXX indicates that copper is the main alloying element. Manganese for 3XXX, silicon for 4XXX, magnesium for 5XXX, magnesium and silicon for 6XXX, zinc for 7XXX, lithium for 8XXX, and unused series for 9XXX are main alloying elements. In industry, low carbon steels have been commonly used for a long time due to their excellent formability at room temperature, strength, good surface finish, and low cost. How￾ever application of the aluminum and its alloys in this field were ranked far behind steels because of cost and formability issues, despite their high-strength-to-weight ratio and excel￾lent corrosion resistance. For expanding use of aluminum alloys or replacing steels in many areas, however, there have been challenging formability problems for aluminum alloys to overcome. The formability of the aluminum alloys at room temperatures is generally lower than at both cryogenic and elevated temperatures. At cryogenic temperatures, the ten￾sile elongation is significantly increased for many aluminum alloys especially 5XXX series alloys and is related to the enhancement of work hardening, while at elevated temper￾atures it is mainly due to the increased strain rate hardening. Forming at cryogenic temperatures is technologically more challenging than at high temperatures. At hot forming tem￾peratures, other issues should also be taken into consideration such as creep mechanisms which may affect the forming deformation and cavitations at grain boundaries which may induce premature failure at low strain rates. 2. Aluminum for passenger vehicles Lightweight vehicles have become a key target for car man￾ufacturers due to increasing concerns about minimizing environmental impact and maximizing fuel economy without sacrificing the vehicle performance, comfort, and marketabil￾ity (Cole and Sherman, 1995). Aluminum will probably play an important role in the future car generations. Its material properties give some advantages and open the way for new applications in the automotive industry (Carle and Blount, 1999). As a result of the developments in the aluminum indus￾try, improving the mechanical properties of the aluminum alloys by adding various alloying elements increased the application area of these alloys in automotive and aerospace industries (Richards, 1900). Design of aluminum structures can also have a big influence on the sustainability of a car. Some of the important design aspects of a car which influence the environment are weight, aerodynamic and roll-resistance. DHV Environment and Transportation Final Report indicates that the material has a big influence on the car weight. (DHV Environment and Transportation Final Report, 2005). Lightweight car consumes less material resources in the long run (300,000 km), although it would cost about 30% more than the conventional car. Therefore, its production would decrease employment in the car industry by about 4% over a decade while increasing the employment in the short term (Fuhrmann, 1979). Fig. 1 – Average use of aluminum (International Aluminum Institute (IAI), 2002; Martchek, 2006; Mildenberger and Khare, 2000; Schwarz et al., 2001). Aluminum alloys are effective materials for the reduction of vehicle weight and are expanding their applications. Fig. 1 illustrates the usage of aluminum for European and Ameri￾can vehicles over years. In addition to USA and Europe, Japan has recently increased their aluminum alloy usage. Analysts expect that the aluminum alloys usage in Japan Automotive Industry will reach 1.5 million tons by 2010. Assuming vehi￾cle production holds steady at around 10 million units, the average yearly growth will be around 2.5% (McCormick, 2002). As shown in Fig. 1, the amount of aluminum used in 1960 is substantially low. The main reasons are forming difficul￾ties of aluminum alloys at that time and the smaller range of alloys available. The demand for aluminum alloys as light weight materials has increased in recent years. Fig. 2 demon￾strates the amount of produced aluminum products in the world. In the past, the main aluminum products were produced by casting such as engines, wheels, exhaust decor; how￾ever nowadays wrought aluminum products are finding more applications in sheets including exterior panels such as hoods and heat insulators, in extrusions including bumper beams, and in forgings including suspension parts Fig. 2. One of the most important benefits of using aluminum alloys in automotive industry is that every kg of aluminum, which replaces 2 kg of steel, can lead to a net reduction of 10 kg of CO2 equivalents over the average lifetime of a vehi￾cle (Ungureanu et al., 2007). In Fig. 3, the effects of the car components on CO2 emissions are shown. CO2 emission is Fig. 2 – Aluminum products for automobile over years (Cole and Sherman, 1995; Inaba et al., 2005; Patterson, 1980; Miller et al., 2000; Turkish Statistical Institute, 2004)