Sedat ARAS, Rukiye ERTAN, Hande GÜLER ÖZGÜL

Elektrik direnç nokta kaynağı ile birleştirilen yüksek mukavemetli çeliklerin mekanik özelliklerinin incelenmesi

Bu çalışmada farklı kalınlıklardaki DP 800, Usibor 1500 ve Ductibor 500P olmak üzere üç farklı yüksek mukavemetli çelik sac malzeme elektrik direnç nokta kaynağı ile birleştirilmiştir. Kaynak işlemi elektrik akımı, basıncı ve süresi gibi sabit parametreler altında farklı malzeme kombinasyonlarında yapılmıştır. Aynı ve farklı malzeme çiftleri için bindirme şeklinde elektrik direnç nokta kaynağı uygulanarak standartlara uygun çekme numuneleri hazırlanmıştır. Bağlantıların mekanik özellikleri sertlik ve çekme-makaslama testleri ile değerlendirilmiştir. Elde edilen sonuçlar Ductibor 500P malzemenin kaynak sonrasında en yüksek mukavemet ve sertlik değerlerine sahip olduğunu göstermiştir. Ayrıca farklı tür çelikler birbirileriyle kaynak edildiğinde ulaşılan maksimum çekme-makaslama kuvveti ve uzama miktarı aynı tür malzemelere göre daha yüksek değerlerde elde edilmiştir.

Anahtar Kelimeler:

DP 800, Usibor 1500, Ductibor 500P, Elektrik direnç nokta kaynağı, Vickers sertlik testi, Çekme-makaslama testi

Investigation of mechanical properties of high strength steel welded by resistance spot welding

In this study, DP 800, Usibor 1500 and Ductibor 500P three different high strength steel sheet materials with different thicknesses were joined with electrical resistance spot welding. Welding process is carried out in different material combinations under constant parameters such as electric current, pressure and duration. Tensile specimens for the same and different material pairs welded by resistance spot welding in the form of overlay were prepared according to the standards. Mechanical properties of the welded specimens were evaluated by hardness and tensile-shear tests. The results show that Ductibor 500P material has the highest strength and hardness values. Furthermore, when different types of steels are welded together, the maximum tensile-shear force and elongation achieved are higher than those of the same type of materials.

Keywords:

DP 800, Usibor 1500, Ductibor 500P, Resistance spot welding, Vickers hardness, Tensile-shear test,

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