KAYNAK İLERLEME HIZININ AISI 316L PASLANMAZ ÇELİK LAZER KAYNAKLI BİRLEŞTİRMELERİNİN MEKANİK VE MİKROYAPI ÖZELLİKLERİNE ETKİSİ

Öz

Bu çalışmada, AISI 316L (X2CrNiMo17-12-2) östenitik paslanmaz çelik levhalar CO₂ lazer ışını kaynak yöntemi ile birleştirilmiştir. Kaynak işlemi %50 Ar+%50 He gaz korumalı ortamda, 3500W lazer gücüyle ve 90-180-270 cm/dk farklı kaynak ilerleme hızlarında yapılmıştır. Numuneler otomatik olarak alın alına yatay pozisyonda ve ilave metal kullanılmadan birleştirilmiştir. Kaynaklı birleştirmelerin mekanik özelliklerini belirleyebilmek için çekme, çentik darbe ve üç nokta eğme testleri uygulanmıştır. İlave olarak kaynaklı bağlantıların sertlik ölçümü kaynak yönüne dik kesitten gerçekleştirilmiştir. Mikroyapı karakteristikleri ise Optik mikroskop, Taramalı Elektron Mikroskobu (SEM), Enerji Dağılımlı X-Işını Spektroskopisi (EDS), Elemental haritalama ve X-Işını Difraksiyonu (XRD) vasıtasıyla incelenmiştir. Yapılan bu araştırmanın sonucunda, lazer kaynak ilerleme hızının artmasıyla hızlı soğuma sonucunda mekanik özelliklerin iyileştiği ve kaynak metali mikroyapı morfolojisinin değiştiği tespit edilmiştir.

Anahtar Kelimeler

• Lazer ışın kaynağı
• AISI 316L
• kaynak ilerleme hızı
• mekanik özellikler
• mikroyapı

EFFECT OF WELDING SPEED ON THE MECHANICAL PROPERTIES AND MICROSTRUCTURE OF LASER WELDED AISI 316L STAINLESS STEEL

Öz

In this study, AISI 316L (X2CrNiMo17-12-2) austenitic stainless steel plates were joined with CO2 Laser Beam Welding (LBW) method. The welding process were carried out in 50% Ar+50% He shielding gas atmosphere by using 3500W laser power for 90-180-270 cm/min different welding speeds. The samples were joined autogenously in butt welding position without using filler metal. In order to determine the mechanical properties of welded joints, the tensile, charpy impact and three point bending tests were applied. In addition, the hardness of the welded sample was measured on the cross section. The microstructure characterization of welded samples was carried out using with optical microscope, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), elementel mapping and X-ray diffraction (XRD) analysis. As a result of this study, it was found that the mechanical properties of AISI 316L weldment recovered and the microstructure morphology of weld metal altered by increasing laser welding speed due to high cooling rate.

Anahtar Kelimeler

• Laser beam welding
• AISI 316L
• welding speed
• mechanical properties
• microstructure

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