This standard is issued under the fixed designation A ; the number immediately following 1 These practices are under the jurisdiction of ASTM Committee A01 on Steel, containing welds should be cut so that no more than 13 mm (1⁄2. Fast, high-quality ASTM A intergranular corrosion testing run by corrosion experts. ASTM has standardized the test procedure and the specifications are detailed in ASTM A standard (ASTM, ) and ASTM G standard (ASTM.
||10 October 2005
|PDF File Size:
|ePub File Size:
||Free* [*Free Regsitration Required]
This practice includes boiling the sample for 24 to hours in the solution above, and measures the materials performance quantitatively. Each ASTM A Practice specification includes a list of the grades of stainless ast and the acceptable etch structures for the specific alloys. See Appendix X1 for information regarding test selection. The test uses a visual inspection of the surface of the bent specimen to determine pass or fail.
The weight loss is calculated after each step, and reveals if the sample has been properly heat-treated. This abstract is a brief summary of the referenced standard.
ASTM A Intergranular Corrosion Testing and Analysis
The oxalic acid test is commonly used before the Strauss test to determine if a sample is susceptible; samples that pass method A will generally show low corrosion rates in the Strauss test. These tests are often run as a qualification test to ensure each batch of stainless steel is properly prepared. The inch-pound equivalents are in parentheses and may be approximate. Please share this page: A recent publication on intergranular corrosion.
Corrosione intergranulare acciai inox austenitici ASTM A
It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Practice A, the oxalic acid etch test is used as a rapid technique to screen samples of certain stainless steel grades to ensure they are not susceptible to intergranular attack sensitization. G2MT Labs is one of the few labs to offer all five ASTM A corrosion testing practices, as well as the expertise to help you determine which tests to use, what to do if a test fails, and other corrosion consulting as needed.
It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. These tests do not provide a basis for predicting resistance to forms of corrosion other than intergranular, such as general corrosion, pitting, or stress-corrosion cracking.
In everyday applications, corrosion varies by materials and solutions.
How do you select the right ASTM corrosion testing method for your material? The first and fastest step is the ASTM A Practice A, a rapid same-day screening method in Oxalic acid to determine the susceptibility to intergranular corrosion. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. The test is generally performed for acceptance of materials, but not sufficient for rejection of materials.
Some specific hazards statements are given in Historical Version s – view previous versions of standard Work Item s – proposed revisions of this standard Translated Version s: This specification covers the standard practices for detecting susceptibility to intergranular attack in austenitic stainless steels. If you are not sure, please contact us for assistance.
Duplicate samples from both sides of a sheet sample are evaluated to determine if carburization results in intergranular attack. The Huey test works well to analyze chromium depleted regions and intermetallic precipitates, such as sigma phase, and is also used for materials in strongly oxidizing environments such as nitric acid. The chart below comes from the ASTM A standard for selection of the appropriate test by alloy a622-13.
Practice E, the Strauss test, is performed to assess attack associated with chromium-rich carbide formation; it does not detect susceptibility to sigma phase formation. Contact us now for pricing or a quote!
If materials with incorrect heat treatment enter service, they are liable to crack or fail by intergranular corrosion IGC much more rapidly than properly treated materials; ASTM A is a screening test to help find batches that asmt incorrectly processed.
Resistance to Intergranular Corrosion of Austenitic Stainless Steels
The etch structure types used to classify the specimens are: It is typically used for stainless alloys such as andCr-Ni-Mo stainless alloys, and nickel alloys to evaluate the intergranular attack associated with the precipitation of chromium carbides at grain boundaries.
For example, in highly oxidizing solutions, intergranular attack can occur due to intermetallic phases, while attack of carbides may occur somewhat less oxidizing solutions.
Methods asm preparing the test specimens, rapid screening tests, apparatus setup and testing procedures, and calculations and report contents are described for each testing practice. The bent samples are examined at low magnification, where the appearance of cracks or fissures indicate intergranular attack.