ASTM G_Laboratory Immersion Corrosion Testing of Metals. August 18, | Author: Description. Designation: G 31 – 72 (Reapproved ). Buy ASTM G() Standard Practice for Laboratory Immersion Corrosion Testing of Metals from SAI Global. Offering ASTM G31 corrosion testing + modified tests to fit your needs and budget . Rapid, high-quality service by experts.
|Country:||Saint Kitts and Nevis|
|Published (Last):||9 November 2015|
|PDF File Size:||9.10 Mb|
|ePub File Size:||9.30 Mb|
|Price:||Free* [*Free Regsitration Required]|
Molarity and normality are also helpful in defining the concentration of chemicals in some test solutions. The procedures for determining these values are shown in detail in Test Methods E 8. The total surface area of a circular specimen is given by the following equation: Generally, if cracking is observed on the coupon, it can be taken as positive indication of susceptibility, whereas failure to effect this phenomenon simply means that it did not occur under the duration and specific conditions of the test.
The density in the constant K cancels out the density in the corrosion rate equation.
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. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters.
With a thickness of approximately 3 mm 0. Please help us to share our service with your friends. Occasional exceptions, in which a large difference is observed, can occur under conditions of borderline passivity of metals or alloys that depend on a passive film for their resistance to corrosion.
It should be observed, however, that galvanic corrosion can be greatly affected by the area ratios of the respective metals, the distance between the metals and the resistivity of the electrolyte. This standard, rather than a standardized procedure, is presented as a guide so asfm some of the pitfalls of such testing may be avoided.
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.
This standard does sstm purport to address all of the safety concerns, if any, associated with its use.
In special cases for example, for aluminum and certain copper alloysa minimum of 24 h storage in a desiccator is recommended. 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.
Please copy and paste this embed script to where you want to embed Embed Script. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Warning—In many cases the corrosion product on the reactive metals titanium and zirconium is a hard and tightly bonded oxide that defies removal by chemical or ordinary mechanical means. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn.
Determination of Metal Corrosion Rate by ASTM G Canadian Laboratory – LCS Laboratory Inc.
However, the calculations must not be based on mass loss except in qualification tests such as Practices Awhich is usually small but on microsections which show depth of attack. This cracking occurs g331-72 conditions of applied or residual tensile stress, and it may or may not be visible to the unaided eye or upon casual inspection. A number in parentheses indicates the year of last reapproval.
Extraneous effects can be encountered if the air stream impinges on the specimens. G 31 — 72 Reapproved Standard Practice for Laboratory Immersion Corrosion G31-722 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. The values given in parentheses are for information only. In practice, only alloys of the same general type should be exposed in the testing apparatus.
Measurement of percent elongation is a useful index of embrittlement. 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. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
Warning- In many cases the corrosion product on the reactive metals titanium and zirconium is a hard and tightly bonded oxide that defies removal by chemical or ordinary mechanical means.
Oxygen saturation is a function of the partial pressure of oxygen g1-72 the gas. A commercial surface may sometimes yield the most significant results. This cannot be evaluated by mass loss alone. Close attention and a more sophisticated evaluation than a simple mass loss measurement are required to detect this phenomenon. Configuration of top to flask is such that more sophisticated apparatus can be added as required by the specific test being conducted.
ASTM G31-72_Laboratory Immersion Corrosion Testing of Metals
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 testmethods of cleaning test specimens, interpretation of results, and calculation of corrosion rates. Most tests related to process equipment should be run with the natural atmosphere inherent in the process, such as the vapors of the boiling liquid. Constant K in Corrosion Rate Equation 3.