ASTM G_Laboratory Immersion Corrosion Testing of Metals – Free download as PDF File .pdf), Text File .txt) or read online for free. ASTM G Other ASTM procedures for laboratory corrosion tests are tabulated in the Appendix. NOTE 1—Warning: In many cases the corrosion product on the reac-. ASTM G Standard Practice for Laboratory Immersion Corrosion Testing of Metals_能源/化工_工程科技_专业资料. 暂无评价|0人阅读|0次.
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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 practice also emphasizes the importance of recording all pertinent data and provides a checklist for reporting test data. The most common testing periods are 48 to h 2 to 7 days. 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.
Careful observation is needed to ensure that pitting does not occur during cleaning. Individual reprints single or multiple copies of this standard may be obtained by contacting ASTM at the above address or at phonefaxor service astm.
ASTM G31 – 72() Standard Practice for Laboratory Immersion Corrosion Testing of Metals
There are a number of other special types of phenomena zstm which one must be aware in the design and interpretation of corrosion tests.
If metallic contamination of the stamped area may in? In many such cases, corrosion rates are established by mass gain rather than mass loss. These changes should be determined if possible.
A large surface-to-mass ratio asrm a small ratio of edge area to total area are desirable. Measurement of percent elongation is a useful index of embrittlement. This can be accomplished by analysis of the solution after corrosion has occurred. Any necessary distortion of the test conditions must be considered when interpreting the results. These factors include specimen preparation, apparatus, test conditions, methods of cleaning specimens, evaluation of results, and calculation and reporting of corrosion rates.
This standard is subject to revision at any time by the responsible technical committee and must be reviewed every? The density in the constant K cancels out the density in the corrosion rate equation. For proper interpretation of the results obtained, the speci?
The behavior of the specimens in this galvanic couple are compared with that of insulated specimens exposed on the same holder and the galvanic effects noted. Oxygen saturation is a function of the partial pressure of oxygen in the gas. The choice of a speci?
Calculating Corrosion Rates Active view current version of standard. The mass loss during aastm test period can be used as the principal measure of corrosion. 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.
Therefore, at least duplicate specimens should normally be exposed in each test. NOTE 1—If desired, these constants may also be used to convert corrosion rates from one set of units to another. 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 of certain alloys, such as the AISI Type series stainless steels in chloride contaminated environments.
ASTM G Standard Practice for Laboratory Immersion Corrosion Testing of Metals_百度文库
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.
G 31 — 72 Care should be used to avoid the removal of asrm metal. However, some of the corrosion products usually adhere to the specimen as a scale and the corrosion rate calculated from the metal content in the solution is aastm always correct. Preferably, the use of a re? The actual time of contact of the metal with the solution must also be taken into account.
Interpretation of Results In many such cases, corrosion rates are established by mass gain rather than mass loss. If clad alloy specimens are to be used, special attention must be given to ensure that excessive metal is not removed.
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.