Direct tension stress corrosion test

Recommended practice for examination and evaluation of pitting corrosion Test method for determining susceptibility to stress corrosion cracking of high-strength aluminium alloy products Test method for pitting and crevice corrosion resistance of stainless steels and related alloys by the use of ferric chloride solution Recommended practice for preparation and use of direct tension stress corrosion test specimens... 

G49, Standard Practice for Preparation and Use of Direct Tension Stress-Corrosion Test Specimens, ASTM, West Conshohoken, PA, 1995. 

Fig. 9.5 Tensile specimen used in constant-deformation test [17]. Reprinted, with permission, from ASTM G 49-85 Standard Practice for Preparation and Use of Direct Tension Stress-Corrosion Test Specimens, copyright ASTM international, West Conshohocken, PA.

ASTM G 49, Recommended Practice for Preparation and Use of Direct Tension Stress-Corrosion Test Specimens— This presents the design, preparation, and use of ASTM standard tension test specimens for investigating susceptibiUty to SCC. Specimens are generally tested in a selected environment imder axial load conditions until fracture occurs. This standard describes the apparatus for providing the load to the stressed specimens along with exposure considerations and inspection methods. 

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). 

Zirconium and its alloys are susceptible to stress corrosion cracking (SCC) in such environments as Fe - or Cu -containing chloride solution, CH3OH -H hahdes, concentrated HNO3, halogen vapors, and liquid mercury or cesium [4,5]. Common test methods, e.g., U-bend, C-ring, split ring, direct tension, double cantilever, and slow strain rate tension, have been used to determine zirconium s susceptibility to SCC. 

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