Study in the Methods of Result Assess of Intergranular Corrosion in Stainless Steels

The bending area of austenitic stainless steel, duplex stainless steel, stainless steel weld overlay and stainless steel welded joint which had crack or fracture after intergranular corrosion testing were studied by metallographic, electronic scanning and transmissiom microscope.The results show that the test evaluation methods among GB4334-2008 E or ASTM262-E standards are difficult manipulative, which will lead to disputed assessment results frequently.The test evaluation methods among the standards should be more detailed than the existing, one telling how to evaluate the results in words or pictures.It is necessary to analyze the cracks or fractures by means of 100~500 times metallographic microscope, or even SEM and TEM if the results are disputed.It is important to summarize low power failure morphology characteristics in the base of high power micro analysis for easy use of the standards.