Pitting and Crevice Corrosion Testing

Understanding the corrosion challenges and the susceptibility of a material can help foresee issues before they emerge, particularly pitting and crevice corrosion, which can be difficult to detect and predict. Energy, Aerospace, Infrastructure, Environmental, and Industrials manufacturers can all benefit from Infinita lab pitting and corrosion testing services for their metal and alloy products. 

Corrosion testing using the ASTM G48 A, C, and E procedures for pitting

Pitting corrosion testing is conducted at test temperatures of up to 60 °C, in accordance with ASTM G48 A. The materials are immersed in a solution of 6 wt% ferrite chloride for a total of 72 hours (usually 24 hours). The ASTM A923 procedure – C test is a modification of the ASTM G48-A test for duplex stainless steels. 

To find out what temperature causes pitting in a material, a method called Critical Pitting Temperature (CPT) is utilized. In CPT, specimens are heated gradually over the course of 72 hours. When pitting appears, the temperature is raised and noted as the Critical Pitting Temperature (CPT). 

The ASTM150 electrochemical test method can be used instead of the G48 procedures to identify the onset of pitting. This technique entails polarizing the specimen and gradually increasing the temperature of the solution to detect the CPT.

Corrosion testing in crevices using the ASTM G48 B, D, and F standards

At the test temperature, usually up to 60°C, Infinita Lab conducts crevice corrosion testing in line with ASTM G48 B. The materials are immersed in a solution of 6 wt% ferrite chloride for a total of 72 hours (usually 24 hours). 

A Critical Crevice Temperature (CCT) test can be used to find the temperature at which cracks begin to form. Stainless steel can be tested using Method D of ASTM G48, while nickel alloys are tested using Method F. Using CCT, temperatures are gradually increased over the course of 72 hours to expose specimens to the point when a crack appears.

Because of our extensive experience with corrosion testing programs and familiarity with industry standards, we can recommend an approach that will yield the most accurate results for your products. If you want to save time and money on your next project, it’s vital that you select the appropriate testing approach the first time around. 

Corrosion in cracks A Standard Test Method (ASTM) G78 

Infinita Lab provides crevice corrosion testing at test temperatures up to 60 degrees Celsius, in compliance with ASTM G78. Castellated washers (MCAs) with 20 contact points per washer are applied to the surface of the specimen and subjected to a chloride-containing environment (seawater) for up to 30 hours (generally 24 hours). The specimens are inspected for crevice corrosion after the testing period has concluded. 

Pitting and crevice corrosion analysis 

The ASTM G46 standard is used in our corrosion labs for testing pitting and crevice corrosion. Electron Scanning Microscopy enables more in-depth analysis.