Elektrod Basıncının Nokta Direnç Kaynaklı DP600 Çeliğinin Mikroyapı ve Sertliğine Etkileri

Yıl 2018, Cilt: 7 Sayı: 2, 194 - 205, 30.12.2018

Muhammed Elitaş , Bilge Demir

https://doi.org/10.17100/nevbiltek.403814

Cited By: 1

Öz

Bu
çalışmada DP600 otomotiv sac çeliğinin sabit kaynak akımı ve sabit kaynak
süresinde, 5 farklı elektrot basıncı için nokta direnç kaynaklı birleştirmeleri
gerçekleştirilmiş, elektrod basıncının mikroyapı ve sertliğe olan etkileri
araştırılmıştır. Mikroyapı ve sertlik, malzeme özelliklerine ve başta ısı
girdisi olmak üzere kaynak parametrelerine bağlı olarak değişmektedir. Elektrod
basıncı, nokta direnç kaynak (NDK) işlemi süresince kaynak temas yüzeyi ve ısı
transferine etki etmektedir. Bu iki faktör makroyapı-mikroyapı-mekanik
özellikler ilişkisi dolayısıyla kaynak performansı üzerinde çok etkilidir.
Deneysel sonuçlar, NDK termal gradyantının tersine malzeme sertliğinin ana
metal, ITAB ve kaynak metali boyunca arttığını göstermiştir. İlave olarak NDK
baskı kuvvetinin artması ile de DP600 numunelerinin ITAB ve kaynak metalindeki
martensit hacim oranı artmış ve bu doğrultuda sertliğinde artış görülmüştür. En
büyük nugget çapı en yüksek NDK baskı kuvveti numunelerinde tespit edilmiştir.
Ayrıca, sonuçlar ve literatür karbon eşdeğeri ve soğuma hızı açısından
irdelenmiştir.

Anahtar Kelimeler

DP600, NDK, mikroyapı, sertlik

Kaynakça

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