Abstract. A detailed study of AISI and stainless steels (SSs) has been conducted to correlate the degree of sensitization (DOS) measured by the. ASTM a Test, Intergranular Corrosion, IGC, ASTM A Practice, Copper – Copper Sulfate – 16% sulfuric acid, ASTM A – Practice E (Strauss Test). ASTM A Practice E test. This practice describes the procedure by which the copper-copper sulfate% sulfuric acid test is conducted to determine .

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In SEM analysis, intergranular corrosion is clear by pracgice dark lines where the grain boundaries are eaten away. This website uses cookies to improve user experience. The Oxalic Acid test is also only applicable to corrosion associated with chromium carbide precipitates and is only useful for specific material grades.

Intergranular practuce occurs as a result of precipitation of nitridescarbidesand other intermetallic phasessuch as sigma phase, that occurs along the grain boundaries. Test sample was etched using Oxalic Acid asgm electrolyte etching. Although this test method uses some similar equipment, this method should not be confused with Test Method G This simple etching technique is used as a quick screening method to ensure that a material is free of intergranular corrosion susceptibility.

The level of corrosion is determined by mass loss. The test uses a visual inspection of the surface of the bent specimen to determine pass or fail.

ASTM A Intergranular Corrosion Testing and Analysis

At the conclusion off the test, specimens are either visually examined or measured for weight loss and compared to an established corrosion rate for that specific material type. The test evaluates the resistance of extra-low-carbon steels to sensitization and intergranular attack from welding or heat treatment processes.

Methods for preparing the test specimens, rapid screening tests, apparatus setup and testing procedures, and calculations and report contents are described for each testing practice. The etch structure types used to classify the specimens are: These practices include five intergranular corrosion tests, namely: 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 r.


Intergranular Corrosion Testing: An Overview of ASTM A262

A recent practide on intergranular corrosion. Please share this page: Metals like stainless steels and aluminum contain elements such as niobium and chromium, often integrated because of their natural corrosion resistance. Our Corrosion Test services and capabilities are as follows: In many cases we can reduce that to as little as 24 hours more than the required testing time if you need fast results.

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. Edges shall be rounded and a fine final polish is required at all surface exclude the weld cap and root area. This specification covers the standard practices for detecting susceptibility to intergranular attack in austenitic stainless steels.

ASTM A Testing: An Overview of Intergranular Corrosion | Element

This abstract is a brief summary of the referenced standard. However, when a material is exposed to high temperatures for long periods of time, a process called sensitization may occur. By using our website you consent to all cookies in accordance with our Cookie Policy.

Like what you saw? For example, in highly oxidizing solutions, intergranular attack can occur due to intermetallic phases, while attack of carbides may occur somewhat less oxidizing solutions. The samples are weighed at each interval to determine mass loss and degree of susceptibility to intergranular attack.

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. This method is a hour boiling test for “as received” specimens of stainless steel. Learn more about our laboratories – where they are located; the unique capabilities they have and how they can help you solve your technical and commercial challenges. This method is preferable for chromium depletions and corrosion in intermetallic phases.

Strauss test specimens are boiled in a Copper Sulfate – Sulfuric Acid mixture for 15 hours. Some specific hazards statements are given in A bend test followed by a visual or micro-examination are used to determine “Pass” or “Fail” of test specimens.


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.

Choosing the correct method s rely on a complete understanding of your material and processes, as well as the concept of corrosion itself.

A different ASTM A test method must be used to quantify the level of corrosion or to disqualify a material for use. 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. Sample condition before soaking in Ferric chloride solution. Because it can be run quickly for screening, we often run this test first.

ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date. Work Item s – proposed revisions of this standard.

To understand intergranular corrosion testing or intergranular attack commonly abbreviated as IGC or IGAit is important to understand what causes the process to occur. If materials with incorrect heat treatment enter service, they are liable to crack or fail by intergranular praxtice IGC much more rapidly than properly treated materials; ASTM A is a screening test to help find batches that are incorrectly processed.

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 aztm test fails, and other corrosion consulting as needed.

Historical Version s – view previous versions of standard. Praxtice specify the maximum allowable corrosion rate and any available data on the sensitizing heat treatment performed.

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