1、Standard Method of Test for Sensitivity of Stainless Steel to Intergranular Attack AASHTO Designation: T 372M/T 372-171Technical Section: 4f, Metals Release: Group 2 (June 2017) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.
2、C. 20001TS 4f T 372M/T 372-1 AASHTO Standard Method of Test for Sensitivity of Stainless Steel to Intergranular Attack AASHTO Designation: T 372M/T 372-171Technical Section: 4f, Metals Release: Group 2 (June 2017) 1. SCOPE 1.1. This method covers the procedures to be used to evaluate the sensitivity
3、 of stainless steel products in Table 1 of M 334M/M 334 to intergranular attack in austenitic or ferritic stainless steels or the formation of a detrimental intermetallic phase in a duplex stainless steel. It is important to note that these tests evaluate certain detrimental effects that can occur i
4、n stainless steels that could reduce the functional life of the steel. These tests are not designed for estimating the service life of stainless steel products in M 334M/M 334 Table 1 embedded in concrete. 1.2. This corrosion test shall be performed biannually or when requested by purchaser on reinf
5、orcing steel materials listed in M 334M/M 334 Table 1 with a chromium concentration greater than 12.5-wt %, with the results available to the customer on request. The tests listed in this specification shall apply only when specified in the purchase order. 1.3. The values stated in either SI or inch
6、-pound units shall be regarded separately as standard. The inch-pound units are shown in brackets. The values stated might not be exact equivalents; therefore, each system must be used independently of the other. 1.4. This standard may involve hazardous materials, operations, and equipment. This sta
7、ndard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this procedure to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AA
8、SHTO Standard: M 334M/M 334, Uncoated, Corrosion-Resistant, Deformed and Plain Chromium Alloyed, Billet-Steel Bars for Concrete Reinforcement and Dowels 2.2. ASTM Standards: A262, Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels. A763, Standard P
9、ractices for Detecting Susceptibility to Intergranular Attack in Ferritic Stainless Steels. A923, Standard Test Methods for Detecting Detrimental Intermetallic Phase in Duplex Austenitic/Ferritic Stainless Steels. 2017 by the American Association of State Highway and Transportation Officials. All ri
10、ghts reserved. Duplication is a violation of applicable law.TS 4f T 372M/T 372-2 AASHTO 3. TEST APPARATUS 3.1. For austenitic stainless steels, guidance is provided in ASTM A262. 3.2. For ferritic stainless steels, guidance is provided in ASTM A763. 3.3. For duplex austenitic/ferritic stainless stee
11、ls, guidance is provided in ASTM A923. 4. TEST SPECIMENS 4.1. For austenitic stainless steels, guidance is provided in ASTM A262. 4.2. For ferritic stainless steels, guidance is provided in ASTM A763. 4.3. For duplex austenitic/ferritic stainless steels, guidance is provided in ASTM A923. 5. PROCEDU
12、RE 5.1. Testing should be conducted according to the type of stainless steel as follows: 5.2. Austenitic stainless steels shall be tested in accordance with Practice E, in conjunction with Practice A, of ASTM A262. 5.3. Ferritic stainless steels shall be tested in accordance with Practice Y or Z, in
13、 conjunction with Practice W, of Specification ASTM A763. The stainless steel UNS designation and Table 2 in ASTM A763 shall be used to determine the best test practice, Y or Z. 5.4. Duplex austenitic/ferritic stainless steels shall be tested in accordance with Test Method C, in conjunction with Tes
14、t Method A, of ASTM A923. 6. CALCULATIONS 6.1. For austenitic stainless steels, guidance is provided in ASTM A262. 6.2. For ferritic stainless steels, guidance is provided in ASTM A763. 6.3. For duplex austenitic/ferritic stainless steels, guidance is provided in ASTM A923. 7. REPORT 7.1. For austen
15、itic stainless steels, guidance is provided in ASTM A262. Results from this test should be recorded and provided to the purchaser if requested. 7.2. For ferritic stainless steels, guidance is provided in ASTM A763. Results from this test should be recorded and provided to the purchaser if requested.
16、 7.3. For duplex austenitic/ferritic stainless steels, guidance is provided in ASTM A923. Results from this test should be recorded and provided to the purchaser if requested. 2017 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violat
17、ion of applicable law.TS 4f T 372M/T 372-3 AASHTO 8. PRECISION AND BIAS 8.1. For austenitic stainless steels, precision and bias statements are being determined within ASTM A262 for the practices involving weight loss evaluations. There is no information on precision and bias statements for the visu
18、al evaluations methods A and F within ASTM A262 as the test results are non-quantitative. 8.2. For ferritic stainless steel, there are no precision and bias statements provided in ASTM A763. Depending on the test and alloy, evaluations are accomplished by weight loss determination, microscopical exa
19、mination, or bend tests. The microscopical examination and bend tests are non-quantitative. 8.3. For duplex austenitic/ferritic stainless steels, a precision and bias is not provided within ASTM A923. The tests do not determine the precise nature of the detrimental phase but rather the presence or a
20、bsence of an intermetallic phase to the extent that it is detrimental to the toughness and corrosion resistance of the material. These are qualitative tests. Either a detrimental phase is present or not. The test results are non-quantitative. 9. KEYWORDS 9.1. Austenitic stainless steel; corrosion te
21、st; duplex austenitic/ferritic stainless steel; ferritic stainless steel; intergranular attack; stainless steel reinforcing bars. 1Formerly AASHTO Provisional Standard MP 18M/MP 18, Annex A1. First published as a full standard in 2017. 2017 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.
