ASTM G39 PDF
Standards Related to G39 – G G Standard ASTM Standards Related to Corrosion Testing of Metals · Annual Book of ASTM Standards Online: Hello everyone, I am looking for ASTM G39 – 99() Standard Practice for Preparation and Use of Bent-Beam Stress- Corrosion Test Specimens. Please. ASTM G39 – 99() – 弯曲梁应力腐蚀试验试样制备和使用标准规程.
|Published (Last):||20 May 2011|
|PDF File Size:||14.30 Mb|
|ePub File Size:||16.29 Mb|
|Price:||Free* [*Free Regsitration Required]|
NOTE 8—If the test is to be conducted in an electrolyte, the spacer shall be made of the same material as the specimen or of an electrically nonconducting material such as glass, ceramic, and so forth to prevent galvanic action between specimen and spacer.
3 & 4 POINT BEND FIXTURES – Cortest
It is most useful for detecting large differences between the stress-corrosion cracking resistance aetm a different metals in the same environment, b one metal in different metallurgical conditions in the same environment, or c one metal in several environments. If specimen holders or insulators are made of such materials, the applied stress on the specimen may change appreciably with time.
Thus, the errors in the applied stress are related to those inherent in the use of measuring instruments micrometers, de? The bent-beam specimens are designed for testing at stress levels below the elastic limit of the alloy.
Since stress-corrosion cracking is a function of the total stress, for critical applications and proper interpretation of results, the residual stress before applying external stress or the total elastic stress after applying external stress should be determined by appropriate nondestructive methods, such as X-ray diffraction 1. Hold them in this position by welding the axtm together as shown in Fig.
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. To facilitate calculations, a computer can be used to generate a table for a range of strain?
In both sustained and alternate immersion, the solution volume should be large enough to prevent depletion of corrosive agents. Chemical or electrochemical treatments that produce hydrogen on the specimen surface must not be used on materials that may be subject to embrittlement by hydrogen g339 that react with hydrogen to form a hydride. The bent-beam specimens are designed for testing at stress levels below the elastic limit of the alloy.
Since stress-corrosion cracking is a function of the total stress, for critical applications and proper interpretation of results, the residual stress before applying external stress or the total elastic stress after applying external stress should be determined by appropriate nondestructive methods, adtm as X-ray diffraction 1.
ASTM G39 – 99()_图文_百度文库
If this f39 occurs, either eliminate the crevice or consider a different kind of specimen. For plate material the bent-beam specimen is more difficult to use because more rugged specimen holders must be built to accommodate the specimens.
Link to Active This link will always route to the current Active version of the standard. Historical Version s – view previous versions of standard.
Therefore, the use of bent-beam specimens in the plastic range is not recommended for general use.
ASTM G39 – 99(2016)
For testing in the plastic range, U-bend specimens should be employed see Practice G By proper choice of holder and insulator materials, however, many plastics can be used, especially in short-time tests. This excludes corrosion-reduced sections aztm fail by fast fracture. To stress two-point loaded specimens Fig. This practice applicable to specimens of any metal that are stressed to levels less than the elastic limit of the material, and therefore the applied stress can be accurately calculated or measured Note 1.
The specimen is most easily made from strip or sheet but can be machined from plate, bar, castings, or weldments; wire specimens may be used also. The inch-pound values in parentheses are provided for information. Personnel installing and examining specimens should be cognizant of this possibility and be protected against injury. Current edition approved March 1, For plate material the bent-beam specimen aastm more difficult to use, because more rugged specimen holders must be built to accommodate the specimens.
It should also be noted that presence of voluminous corrosion products may obscure cracks, thus making a careful examination mandatory. The two inner supports shall be located symmetrically around the midpoint between the outer supports. In alternate immersion, expose the specimen to allow complete drainage and drying of the surface. Link to Active This link will always route to the current Active version of the standard.
The inch-pound equivalents in parentheses are provided for information. Information is available from http: For plate material the bent-beam specimen is more difficult to use because more rugged specimen holders must be built to accommodate the specimens.
Once cracking has initiated, the state of stress at the tip of the crack as well as in uncracked areas has changed, and therefore, the known or calculated stress or strain values discussed in this practice apply only to the state of stress existing before initiation of cracks.
A convenient stressing jig is shown in Fig. Stress calculations by this practice are not applicable to plastically stressed specimens. This relationship can be used as a simple check to ensure that the maximum stress does not exceed the proportional limit.
However, for meaningful interpretation, comparisons should be made only among tests employing crack detection methods of equivalent sensitivity.
In addition to the cracking time the following data shall be reported: Originally approved in It is the nature of these practices that only the applied stress can be calculated.
In elevated-temperature tests, make arrangements to re? The common parameter in these equations is the modulus k of the elliptic integrals.
Stress calculations by this practice are not applicable to plastically stressed specimens. However, unless directly related to practical conditions of usage, misleading failures may ensue. In some cases for example, very thin sheet or small diameter wire it is possible to form a U-bend and produce only elastic strain.
Historical Version s – view previous versions of standard.