SERKAN TOROS, Remzi Ecmel ECE, FAHRETTİN ÖZTÜRK, MAHMUT ALKAN

5754-O Al-Mg alaşımında ön gerilmenin geri esnemeye etkisinin deneysel ve sonlu elemanlar yöntemiyle incelenmesi

Bu çalısma kapsamında otomotiv endüstrisinde oldukça yaygın kullanılmaya baslanan alüminyum magnezyum alasımlarından 5754-O alasımının 60o’lik V sekilli kalıpta geri esneme davranısı incelenmistir. Malzemelere % 1, 3, 5, 7, 9 ve 11’lik ön gerilmeler uygulayarak malzemelerin akma noktaları degistirilmis ve bu ön gerilmelerin geri esneme üzerindeki etkileri deneysel olarak incelenmistir. Ayrıca çalısmalar ETA/Dynaform sac sekillendirme simülasyon programında analiz edilerek deneysel sonuçlarla karsılastırılmıstır. Sonuç olarak uygulanan ön gerilmenin geri esnemeye pozitif etkisi tespit edilememistir. Sonlu elemanlar programıyla yapılan simülasyonların deney sonuçlarına göre kabul edilebilir yakınlıkta oldugu görülmüstür.

The investigation of prestraining on springback behavior of 5754-O Al-Mg alloy experimentally and finite element model

In this study, springback behavior of 5754-O from aluminum magnesium alloys which is started to use extensively in automotive industry was investigated at 60o V shaped die. The yield point of the material was changed by performing prestrainings about 1, 3, 5, 7, 9, 11 % and the effects of these prestrainings on springback behavior of the material are investigated experimentally. Besides that these studies were analyzed by using ETA/Dynaform sheet metal forming simulation program and compared with experimental results. Results show that the prastraining does not have positive effects on springback. The results of finite element simulations are acceptable far from the experimental results.

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