ESD Tekniği ile WC Kaplanmış AISI 1010 Çelik Sacların Nokta Kaynağı

Abstract

Değişik yöntemlerle yapılan yüzey kaplamaları, metalik ve metalik olmayan malzemelerin yüzey özelliklerini değiştirmekte ve aşınma direnci gibi özellikleri iyileştirmektedir. Sert bir fazla yüzey kaplama sonucunda, yüzey aşınmaya karşı korunmakta ancak ark ve yüksek enerjili kaynaklı birleştirmede sorun çıkabilmektedir. Kaplama tabakasının genel özelliklerinin, kaynak işlemi sonrasında nasıl değiştiğinin yanında, kaynaklı birleştirmenin mekanik özellikleri de önemlidir. Bu çalışmada, sabit akım, farklı frekans ve voltajlarda AISI 1010 çeliği üzerine ESD yöntemi ile tungsten karbür (WC) kaplama işlemi yapılmış ve daha sonra iki aynı özellikteki numune, sabit akım ve baskı kuvvetinde nokta kaynağı ile birleştirilmiştir. Kaynak bölgesini ortaya çıkarmak için numuneler ikiye bölünmüştür, daha sonra kalıba alınarak ve klasik metalografik işlemler uygulanmıştır. Metalografik işlemler sonrasında kaynak bölgesinde oluşan içyapıları incelemek için optik mikroskop ve Elektron Mikroskopisi ile görüntüler alınmıştır. Sonuçlar, WC kaplı çelik sacların kaynak bölgesinde bölgesel alaşımlamaya sebep olduğunu ve bu nedenle mikro yapılarda ciddi değişiklikler olduğunu göstermiştir.

Keywords

• AISI 1010
• Düşük Karbonlu Çelik
• Nokta direnç kaynağı
• Elektro-Kıvılcım Biriktirme (ESD)
• Tungsten Karbür (WC) kaplama

Spot Welding of AISI 1010 Steel Sheets Coated with WC by ESD Technique

Abstract

Surface coatings made with different methods change the surface properties of metallic and non-metallic materials and improve properties such as wear resistance. As a result of a hard surface coating, the surface is protected against wear, but problems may arise in arc and high-energy welded joints. Besides how the general properties of the coating layer change after the welding process, the mechanical properties of the welded joint are also important. In this study, tungsten carbide (WC) coating was carried out on AISI 1010 steel by ESD method at constant current using different frequencies and voltages and later two identical specimens were joined by spot welding at constant current and pressure. In order to reveal the welding zone, the samples were sliced into two, and then moulded and classical metallographic processes were applied. After metallographic processes, images were taken with an optical microscope and Electron microscopy to examine the microstructures formed in the weld zone. The results show that WC coated steel sheets cause localized alloying in the weld zone and therefore drastic changes in microstructures.

Keywords

• AISI 1010 steel
• Low carbon steel
• Spot resistance welding
• Electro-Spark Deposition (ESD)
• Tungsten Carbide (WC) Coating

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