Abstract

Welding joints of stainless steels are in practice very sensitive places attacked by local corrosion, such as pitting and crevice corrosion, mostly in chloride containing oxidizing environments. It is caused by different oxidation products created on the surface by welding. Corrosion resistance of stainless steels is affected by quality of passive layer (Cr2O3) which created at normal conditions on air. After welding the steels are heated and on the surface are originated different types of oxides which have not the same protective properties. Resistances to intercrystalline and pitting corrosion of two type of welded stainless steel with different surface finishing were tested. Experimental materials are the austenitic stainless steel AISI 316L (welded by the TIG method in inert Ar atmosphere with filler) and the ferritic stainless steel AISI CA6-NM (welded by the WPS method in inert Ar atmosphere with filler and after welding heat treated). Character of the surface after welding and after mechanical finishing by grinding was evaluated by SEM microscopy, EDX analysis. Corrosion resistance to local forms of corrosion was tested by electrochemical potentiodynamic test and by exposure tests in chloride solutions. The steel AISI CA6-NM was tested in fluvial water to simulate real operation environment. The evaluation is supported by microscopic analysis. Susceptibility to intergranular corrosion was tested too and results detect the dangerous localities for corrosion attack and show increasing of corrosion resistance by surface treatment.

Highlights

  • Stainless steels are considered corrosion resistant construction material

  • Welding joints of them are in practice very sensitive places attacked by local corrosion, such as pitting and crevice corrosion, mostly in chloride containing oxidizing environments

  • Potentiodynamic polarization tests Cyclic potentiodynamic polarization studies were made with a three-electrode system using a computer-controlled potentiostate/galvanostate VSP (Biologic) with the power Sorens SGA (ASTM G5 Standard reference Test Method for Making Potentiostatic and Anodic Polarization measurement) [18].The tests were performed in locality of base material and weld metal

Read more

Summary

SURFACE STATE EFFECT OF WELDED STAINLESS STEELS ON CORROSION BEHAVIOR

Tatiana Liptáková1)*, Martin Lovíšek1), Ayman Alaskari2), Branislav Hadzima3) 1)University of Žilina, Faculty of Mechanical Engineering, Department of Material Engineering, Žilina, Slovakia 2) Department of Mechanical Production Technology, College of Technological Studies, Kuwait 3) Research Centre of the University of Žilina, Žilina, Slovakia

Introduction
Ni Mo Mn C
Unfinished Ground finish
Potentials of WM
Finished surface
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call