AA 5754-O alaşımının ılık derin çekilmesi üzerine kalıp yüzey açısı ve baskı plakası kuvvetinin etkisinin deneysel araştırılması

Bu çalışmada, AA 5754-O alaşımının ılık derin çekilmesine kalıp yüzey açısı, baskı plakası kuvveti ve sıcaklığın etkisinin deneysel olarak belirlenmesi amaçlanmıştır. Bunun için, kalıp yüzeylerine 0-15° arasında açılar verilerek deneyler oda sıcaklığı(OS), 100oC, 175o C ve 250o C sıcaklıklarında, 1,2 kN, 2,4kN ve 3,6 kN baskı plakası kuvvetlerinde gerçekleştirilmiştir. Deneylerde, kalıp boşluğu 1,35 mm, ıstampa ve kalıp radyüsleri ise 8 mm sabit tutulmuştur. Kalıpla iş parçası arasındaki sürtünme kuvvetini düşürmek için yüksek sıcaklık ve baskılar altında özelliğini yitirmeyen MoS2 katı yağlayıcı kullanılmıştır. Yapılan çalışmalar neticesinde et kalınlığı, ıstampa kuvveti ve geri yaylanma üzerine kalıp yüzey açısı ve baskı plakası kuvvetinin etkisinin OS ve 100oC'de daha belirgin olduğu, sıcaklık arttıkça et kalınlığı dağılımınındaha homojen hale geldiği; şekillendirme kuvveti, geri yaylanma miktarı ve sertlik değerinin ise önemli ölçüde düştüğü belirlenmiştir. Yine kap duvarı boyunca sertlik değerinin kap ağzına doğru gidildikçe arttığı ve sıcaklığın önemli etkisinin olduğu görülmektedir.

Experimental investigation of the effects of blank holder force and die surface angle on the warm deep drawing of AA5754-O alloy

In this study, it is aimed to determine the experimental effects of die surface angle, blank holder force andtemperature on the warm deep drawing of AA5754 alloy. For this purpose, the die surfaces were machinedbetween 0-15? and the experiments were performed under 1.2 kN, 2.4 kN and 3.6 kN blank holder forces and at different temperature values, namely; room temperature (RT), 100°C, 175°C, and 250°C. In theexperiments, the die clearance, punch and die radii were kept constant as 1.35 mm and 8 mm, respectively. In order to reduce the friction force between die and blank, MoS2 was used as lubricant due to its hightemperature and pressure resistance. It is experimentally found that the effects of drawing parameters weremore dominant at RT and 100°C. A further increase in forming temperature lead to lower forming forces,springback ratios, hardness and the more homogenous distribution of the wall thickness. It is also observed that the hardness distribution along the cup wall was tendency of increase toward the top of the cup with asignificant effect of temperature.

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