The G48 corrosion test is a standardized test method used to evaluate the resistance of austenitic stainless steels to intergranular corrosion.
Intergranular corrosion occurs when the boundaries between grains in a metal are attacked by a corrosive environment, leading to a loss of mechanical strength and potential failure of the material. Austenitic stainless steels are particularly susceptible to this type of corrosion due to their high chromium and nickel content.
The G48 test involves immersing a sample of the stainless steel in a boiling solution of 6% copper sulfate and 16% sulfuric acid for a period of 24 hours. The test measures the degree of corrosion in the material, particularly at the grain boundaries.
After the test, the sample is examined for signs of corrosion and evaluated based on the amount of corrosion that has occurred. The test results are reported as the weight loss of the sample or as the depth of corrosion penetration.
The G48 test is commonly used in the oil and gas industry, as well as in other industries where austenitic stainless steels are used in corrosive environments. The test is an important tool for evaluating the corrosion resistance of materials and ensuring their suitability for specific applications.