Weldment stress corrosion test specimen

G 58 Practice for the Preparation of Stress-Corrosion Test Specimens for Weldments... 

ASTM G 58, Practice for Preparation of Stress Corrosion Test Specimens for Weldments— This covers the manufacture and application of welded test specimens in stress corrosion testing. This practice is used to evaluate a total weldment, weld metal, or presence of notches and stress risers in weldments with respect to SCC in an environment. In addition, ASTM G 58 contains a method for evaluating the critical stress levels that will produce SCC in a weldment. The specimens are evaluated after exposure to an environment by microscopic methods. This standard includes typical specimens (stressed and tension), welding considerations, test specimen preparation, and inspection after exposure. 

ASTM G 58, Practice for the Prepeuation of Stress Corrosion Test Specimens for Weldments, describes use of aU of the before-mentioned smooth test specimen configurations. It also includes some configurations unique to welding practices, and references citing use of specimens and procedures unique to SCC testing of weldments. 

Smooth specimens can be stressed by a constant load, by constant strain rate, or by constant deflection, which is the usual procedure. Typical specimens are (a) direct tension specimens, (b) C-ring specimens, (c) U-bend sp>ecimens, (d) bent beam specimens, and special techniques for weldments (see ASTM G 49, Practice for Preparation and Use of Direct Tension Stress-Corrosion Test Specimens ASTM G 38, Practices for Making and Using C-Ring Stress-Corrosion Test Specimen ASTM G 30, Practice for Making and Using U-Bend Stress-Corrosion Test Specimens ASTM G 39, Practice for Prep>aration and Use of Bent-Beam Stress-Corrosion Test Specimens and ASTM G 58, Practice for the Preparation of Stress-Corrosion Test Specimens for Weldments, respectively). 

Standard practice for [separation of stress-corrosion test specimens for weldments... 

While many laboratory tests for resistance of metals to stress corrosion cracking have been developed, only a few tests are amenable to actual in-situ testing in seawater. These primarily consist of the exposure of statically stressed type test specimens such as described in ASTM G 30, G 38, G 39, and ISO 7539-2, ISO 7539-3, and ISO 7539-5. In addition, welded specimens such as described in ASTM G 58 are excellent for evaluation of the stress corrosion resistance of weldments in simple immersion tests. Evaluation of corrosion fatigue is usually limited to laboratory testing. 

Corrosion of metals and alloys—Stress corrosion testing—Part 7 Slow strain rate testing Corrosion of metals and alloys—Stress corrosion testing—Part 8 Preparation and use of specimens to evaluate weldments... 

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