Intergranular attack susceptibility

Stress below the proof stress does not normally affect corrosion rates. Cyclic stresses in combination with a corrosive environment (corrosion fatigue) can produce failure at below the ordinary fatigue limit. Alloys susceptible to intergranular attack may corrode faster when stressed (see Section 8.5). 

Investigations into the effects of arsenic and phosphorus in single-phase brasses on their susceptibility to intergranular attack and stress-corrosion cracking in seawater have shown that the normal addition of arsenic to... 

Standard Recommended Practices for Detecting Susceptibility to Intergranular Attack in Stainless Steels, ANSI/ASTM A262 79 (1979)... 

This test has been developed and used by Streicher as a screening test to be used in conjunction with the tedious boiling nitric acid test for assessing the susceptibility of stainless steels to intergranular attack as specified in ASTM A262 1986, and will be considered subsequently in the section concerned with intergranular attack of Cr-Ni-Fe alloys. 

Intergranular corrosion of Fe-Ni-Cr alloys has been the subject of a comprehensive review by Cowan and Tedmon who summarised the various tests used for determining susceptibility (Table 19.3). Of these tests. Nos. 1-5, which are regarded as reliable test procedures by the ASTM, have been incorporated into ASTM A262 1986 Recommended Practice for Detecting Susceptibility to Intergranular Attack in Stainless Steel as follows ... 

Table 19.4 Maximum acceptable evaluation test rates specified by Du Pont for services where susceptible material would be intergranularly attacked ...

In conclusion it must be emphasised again that all the tests used are accelerated tests and only provide information on susceptibility to intergranular attack under the precise test conditions prevailing. They are quality control tests that may be used to demonstrate either that heat treatment has been carried out adequately or that a steel will withstand the test for a certain sensitising heat treatment. 

Practices for detecting susceptibility to intergranular attack in austenitic stainless steels Recommended practice for detection of susceptibility to intergranular corrosion in severely sensitised austenitic stainless steel (intent to withdraw)... 

Practice for detecting susceptibility to intergranular attack in ferritic stainless steels Method of salt spray (fog) testing Method for mercurous nitrate test for copper and copper alloys... 

Recommended practice for applying statistics to analysis of corrosion data Practice for operating light- and water-exposure apparatus (carbon-arc Type) for exposure of nonmetallic materials Method for detecting susceptibility to intergranular attack in wrought nickel-rich, chromium-bearing alloys... 

S.C.C. has been examined as a function of potential in high-temperature water with chlorides present and an increased susceptibility of stainless alloys to intergranular attack was found as the potential was increased. Additional work reported that no intergranular cracking was observed in tests of short duration. 

Sensitisation susceptibility to intergranular attack in a corrosive environment resulting from heating a stainless steel at a temperature and time that results in precipitation of chromium carbides at grain boundaries. 

The selection of a test for detecting susceptibility to intergranular attack can, therefore, not be based solely on convenience, as is implied in the last paragraph of Section 4 of this paper. 

Electrolytic etching of stainless steels has been used industrially to simplify and accelerate the evaluation of stainless steels for their susceptibility to intergranular attack. Be-... 

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