The effects of TIG welding parameters on the microstructure and mechanical properties of AISI 316L stainless steel

In this study, AISI 316L austenitic stainless steel, which is widely used in nuclear power plants due to its high corrosion resistance, is joined by TIG welding method at different welding currents and welding speeds without using additional wire. Then, the heat inputs of the produced welded joints were calculated and macro and microstructure studies, hardness, tensile and bending tests were applied to the samples.. As a result of the microstructure studies, it has been observed that the weld metal has a microstructure consisting of austenite + Skeletal ferrite or delta ferrite. As a result of the hardness tests, it was observed that the hardness decreased with the increase of the welding current, and the hardness increased with the increase of the welding speed. As a result of the tensile tests, similar to the hardness measurements, the tensile strength decreased with the increase of the welding current, while the tensile strength increased with the increase in the welding speed. No tearing or cracking was observed in either the cap twists or the root bends in the 1800 bending tests..

TIG kaynak parametrelerinin AISI 316L paslanmaz çeliðinin mikro yapý ve mekanik özelliklerine etkisi

Bu çalýþmada yüksek korozyon direnci nedeni ile nükleer güç santrallerinde yaygýn bir þekilde kullanýlan AISI 316L östenitik paslanmaz çelik, TIG kaynak yöntemi ile farklý kaynak akýmlarýnda ve kaynak hýzlarýnda, ilave tel kullanýlmadan birleþtirilmiþtir. Daha sonra üretilen kaynaklý birleþtirmelerin ýsý girdileri hesaplanarak, numunelere makro ve mikroyapý çalýþmalarý, sertlik, çekme ve eðme testleri uygulanmýþtýr. Mikroyapý çalýþmalarý sonucunda kaynak metalinin östenit + çatýsal ferrit ya da delta ferritten oluþan bir mikroyapýya sahip olduðu görülmüþtür. Sertlik deneyleri sonucunda kaynak akýmýnýn artmasý ile sertliðin düþtüðü gözlenirken kaynak hýzýnýn artmasý ile de sertliðin yükseldiði belirlenmiþtir. Çekme deneyleri sonuçlarý ise sertlik ölçümleri ile benzerlik göstererek kaynak akýmýnýn artmasý ile çekme dayanýmý düþerken kaynak hýzýnýn artmasý ile çekme dayanýmý artmýþtýr. Yapýlan 1800 eðme testlerinde ise ne kep eðmelerinde ne de kök eðmelerinde herhangi bir yýrtýlma ya da çatlamaya rastlanmamýþtýr.