Fatih AYDEMİR, Betül GÜLÇİMEN ÇAKAN, Ali DURMUŞ, Kadir ÇAVDAR

Hardox 400 Çeliği için Hidrolik Abkant Preste Bükme Parametrelerinin Belirlenmesi

Bu çalışmada, Hardox 400 çeliğinin levha kalınlığı, levha uzunluğu ve mekanik özelliklerine bağlı olarak bükme kuvvetlerini ve zımba yer değiştirmelerini belirlemek için kullanılan özel bir hidrolik abkant pres tabanlı test düzeneği (HPBTS) tasarlanmış ve üretilmiştir. Kurulum, şekillendirme sırasında bükme açısının değişimini algılamak için bir görüntü işleme sistemi ile donatılmıştır. Bükme testleri öncesinde çekme testleri yapılmış ve tespit edilen mekanik özellikler imalatçıların bildirdiği özelliklerle karşılaştırılmıştır. Mekanik özellikler arasındaki farkın bükme parametreleri üzerindeki etkisi araştırılmıştır. Bükme testleri için havada büküm tekniği kullanılmıştır. Deneyler, iki farklı üreticiden temin edilen yassı malzemeler kullanılarak farklı levha kalınlıkları, levha uzunlukları, bükme açıları, bükme hızları ve kanal açıklıkları ile gerçekleştirilmiştir. Bu parametrelerin bükme kuvveti, yer değiştirme ve geri yaylanma açısına etkileri ortaya çıkarılmıştır. Hardox 400 çeliğinin mekanik özelliklerinin üreticiye göre farklılık gösterdiği belirlenmiştir. Ölçülen mekanik özellikler ile imalatçılardan elde edilenler arasındaki farkların, bükme özellikleri üzerinde doğrudan bir etkiye sahip olduğu anlaşılmıştır.

Anahtar Kelimeler:

Hardox 400 çeliği, Hidrolik abkant pres tabanlı test düzeneği, Havada büküm

DETERMINATION OF PRESS BRAKE BENDING PARAMETERS FOR HARDOX 400 STEEL

In the present study, a specific hydraulic press brake based test setup (HPBTS) was designed and manufactured which was used to determine the bending forces and the punch displacements of Hardox 400 steel depending on the plate thickness, plate length and mechanical properties. The setup was equipped with an image processing system to detect the change of the bending angle during forming. Prior to bending tests, tensile tests were carried out and the identified mechanical properties were compared with the ones reported by the manufacturers. The effect of the difference between the mechanical properties on the bending parameters was investigated. Air bending technique was used for bending tests. Experiments were carried out with varying plate thicknesses, plate lengths, bending angles, forming speeds and channel openings using flat materials supplied from two different manufacturers. The effect of these parameters on bending force, displacement and springback angle was revealed. It was shown that the mechanical properties of Hardox 400 steel vary according to the manufacturer. The difference between the measured mechanical properties and the ones obtained from the manufacturers had a direct influence on the bending properties.

Keywords:

Hardox 400 steel, Hydraulic press brake based test setup, Air bending,

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