What is ASTM G28?
INTRODUCTION. The ASTM G28 test methods A and B are utilized in many industries as quality control tests in order to assess the resistance to intergranular corrosion of various stainless steels and nickel-based alloys, such as Alloy 825 and Alloy 625.
What is intergranular corrosion test?
Intergranular Corrosion (IGC) or Intergranular Attack (IGA), is an efficient test for screening a material’s corrosion resistance under certain conditions. Intergranular corrosion refers to material degradation that occurs along the grain boundaries of metallic materials after exposure to a corrosive environment.
What is G48 testing?
ASTM G48 (Standard Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride Solution) [1] is a common test to evaluate the crevice corrosion resistance of stainless steels and nickel alloys.
What are the methods used in identifying the intergranular corrosion?
Susceptibility to intergranular corrosion is determined by immersing test specimens in a given test solution. Two commonly used test solutions are: ferric sulfate-sulfuric acid and mixed acid-oxidizing salt. The susceptibility is determined from the mass loss of specimens from exposure in one of the solutions.
What type of inspection is usually required to detect intergranular corrosion?
Ultrasonic inspection can detect corrosion damage on some surfaces. It is commonly used to detect exfoliation and stress-corrosion cracks.
Is 316 SS austenitic?
Type 316 stainless steel is an austenitic chromium-nickel stainless and heat-resisting steel with superior corrosion resistance as compared to other chromium-nickel steels when exposed to many types of chemical corrodents such as sea water, brine solutions, and the like.
What kind of corrosion test is ASTM G28?
ASTM G28 is a series a test methods designed to detect susceptibility to intergranular corrosion in wrought, nickel-rich, chromium bearing alloys, including but not limited to alloys such as N06625 and N08800. It can also be effective in evaluating the impacts of heat treatment processes on a materials corrosion resistance.
What kind of intergranular test is ASTM G28?
ASTM G28 was designed for nickel-based alloys, and a list of applicable alloys for methods A and B is in the standard. For an alloy that is not listed, look for an alloy with a similar composition to a listed alloy to determine the most suitable test.
Which is the most aggressive intergranular corrosion test?
ASTM A262 method F is a more aggressive version of method E, as are ISO 3651-2 method B and SEP 1877 method 1. None of these are identical and cross substitution of results is not possible. ASTM G28 method B is a more aggressive test than method A and is intended for more corrosion resistant alloys, as listed in the document.
Which is the best corrosion test for aluminum?
Standardized testing for exfoliation corrosion varies based on the aluminum alloy being tested. The main methods of exfoliation corrosion testing are: ASTM G66 – ASTM G66 is designed to determine susceptibility to exfoliation corrosion of 5XXX series aluminum alloys.