Shataur Thank you for interesting in our services. For example, a small coupon is not as prone to exhibit pitting as a large one and it is possible to miss the phenomenon altogether in the corrosion testing g certain alloys, such as the AISI Type series stainless steels in chloride contaminated environments. G practice, rather than a standardized procedure, is presented as a guide so that some of the pitfalls of such testing may be avoided. Masking may also be used to g the desired area ratios but may cause crevice corrosion problems. For relatively soft metals such as aluminum, magnesium, and copperscrubbing with abrasive powder is not always needed and can mar the surface of the specimen. The density in the constant K cancels out the density in the corrosion rate equation.
|Published (Last):||4 May 2019|
|PDF File Size:||8.27 Mb|
|ePub File Size:||14.98 Mb|
|Price:||Free* [*Free Regsitration Required]|
More J This standard, rather than a standardized procedure, is presented as a guide so that some of the pitfalls of such testing may be avoided. It is impractical to propose an inflexible standard laboratory corrosion testing procedure for general use, except for material qualification tests where standardization is required. One purpose for this guide is to promote better correlation of results in the future and the reduction of conflicting reports through a more detailed recording of meaningful factors and conditions.
Scope 1. These factors include apparatus, sampling, test specimen, test conditions test solution composition, temperature, gas sparging, fluid motion, solution volume, method of supporting test specimens, duration of test , methods of cleaning test specimens, interpretation of results, and calculation of corrosion rates. This guide also emphasizes the importance of recording all pertinent data and provides a checklist for reporting test data.
It should be used as a reference to ensure that the test will allow generation of data relevant to the application with the minimum of interferences. The values given in parentheses are for information only. 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.
Determination of Metal Corrosion Rate by ASTM G31-72. Canadian Laboratory
Current edition approved May 1, Published May Originally approved in Last previous edition approved in as G 31 — 72
ASTM G31-72_Laboratory Immersion Corrosion Testing of Metals
Measurement of percent elongation is a useful index of embrittlement. Wstm others are used principally as a supplement to remove heavily encrusted corrosion products before scrubbing. G2MT Laboratories The phenomenon of forming a protective film is observed with many corrosion-resistant materials. However, there are cases where this assumption is not valid. This cracking occurs under conditions of applied or residual tensile stress, and it may or may not be visible to the unaided eye or upon casual inspection. G 31 — 72 Reapproved Standard Practice for Laboratory Immersion Corrosion Testing of Metals1 This standard is issued under the fixed designation G 31; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision.
ASTM G31-72 PDF