Developer Effects of Pre-Heating Applied to the Al7039 Armor Plates Prior to the Friction Stir Welding

In this study, Al7039 plates at certain dimensions were first joined via friction stir welding (FSW) method at room temperature. During this process, thermocouple tips positioned closely to the each side of the weld helped determine temperatures on the advancing and retreating sides. These temperature values were used to estimate pre-heating temperature of the base metal prior to the welding process. After Al7039 plates at identical dimensions were heated to a certain temperature, they were joined using the same welding parameters, and the heat distribution was determined thanks to the thermocouples positioned on the same zones. The heat distribution between two samples which were joined using different heat inputs were analyzed to reveal the impact of this heat distribution on the weld zone via mechanical tests and micro structure images.

Anahtar Kelimeler:

Al7039 alloy, FSW, Pre-heating

Al7039 Zırh Plakalarına Sürtünme Karıştırma Kaynağı Öncesi Uygulanan Ön Isıtmanın Geliştirici Etkileri

Bu çalışmada, belirlenen boyutlarda hazırlanan Al7039 levhalar, öncelikle oda sıcaklığında sürtünme karıştırma kaynağı yöntemi ile birleştirildi. Birleştirme esnasında kaynak başlangıç ve bitiş noktalarına yakın bölgelere yerleştirilen termokupl uçları sayesinde ilerleme kenarı ve yığılma kenarında oluşan sıcaklıklar belirlendi. Elde edilen sıcaklık değerleri kullanılarak kaynak öncesi ana metalin ön ısıtma sıcaklığı tahmin edildi. Aynı boyutlarda hazırlanan Al7039 levhalar belirlenen ön ısıtma sıcaklığına kadar ısıtıldıktan sonra aynı kaynak parametreleri ile birleştirildi vekaynak sırasında aynı bölgelere yerleştirilen termokupllar vasıtasıyla ısı dağılımları belirlendi.Farklı ısı girdileri ile birleştirilen iki numune arasındaki ısı dağılımı incelenerek, bu ısı dağılımının kaynak bölgesindeki etkileri mekanik testler ve mikro yapı görüntüleri ile ortaya konuldu.

Keywords:

Al7039 alaşımı, SKK, Ön ısıtma,

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