1、Standard Specification for Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe Service AASHTO Designation: M 285M/M 285-11 (2015) ASTM Designation: A744/A744M-10 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 2
2、0001 TS-4h M 285M/M 285-1 AASHTO Standard Specification for Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe Service AASHTO Designation: M 285M/M 285-11 (2015) ASTM Designation: A744/A744M-10 1. SCOPE 1.1. This specification covers iron-chromium-nickel alloy, stainless steel castings
3、intended for particularly severe corrosive applications. 1.2. This specification requires postweld heat treatment of all weld repairs affecting surfaces intended to be wetted by the corrosive medium. For applications for which postweld heat treatment is not considered mandatory for retention of acce
4、ptable corrosion resistance, refer to M 163M/M 163. Note 1For general corrosion-resistant alloy castings, reference should be made to M 163M/M 163. For general heat-resistant alloy castings, reference should be made to ASTM A297/A297M. For nickel-base alloy castings, refer to ASTM A494/A494M. 1.3. T
5、he values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the inch-pound units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining va
6、lues from the two systems may result in nonconformance with the standard. SI units are applicable for material ordered to M 285M and inch-pound units for material ordered to M 285. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 163M/M 163, Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion R
7、esistant, for General Application T 244, Mechanical Testing of Steel Products 2.2. ASTM Standards: A262, Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels A297/A297M, Standard Specification for Steel Castings, Iron-Chromium and Iron-Chromium-Nicke
8、l, Heat Resistant, for General Application A494/A494M, Standard Specification for Castings, Nickel and Nickel Alloy A732/A732M, Standard Specification for Castings, Investment, Carbon and Low Alloy Steel for General Application, and Cobalt Alloy for High Strength at Elevated Temperatures A781/A781M,
9、 Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use A957/A957M, Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use 2015 by the American Association of State Highway and Transportation Off
10、icials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 285M/M 285-2 AASHTO E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications E527, Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (
11、UNS) 2.3. American Welding Society Standards: AWS A5.11, Specification for Nickel and Nickel-Alloy Welding Electrodes for Shielded Metal Arc Welding1 AWS A5.14, Specification for Nickel and Nickel-Alloy Bare Welding Electrodes and Rods13. TERMINOLOGY 3.1. Definition of Term Specific to This Standard
12、: 3.1.1. wetted surface, none that contacts a corrosive environment. 4. GENERAL CONDITIONS FOR DELIVERY 4.1. Except for investment castings, castings furnished to this specification shall conform to the requirements of ASTM A781/A781M, including any supplementary requirements that are indicated on t
13、he purchase order. Failure to comply with the general requirements of ASTM A781/A781M constitutes nonconformance with this specification. In case of conflict between the requirements of this specification and ASTM A781/A781M, this specification shall prevail. 4.2. Steel investment castings furnished
14、 to this specification shall conform to the requirements of ASTM A957/A957M, including any supplementary requirements that are indicated in the purchase order. Failure to comply with the general requirements of ASTM A957/A957M constitutes nonconformance with this specification. In case of conflict b
15、etween the requirements of this specification and ASTM A957/A957M, this specification shall prevail. 5. ORDERING INFORMATION 5.1. Orders for material to this specification should include the following, as required, to describe the material adequately: 5.1.1. Description of the casting by pattern num
16、ber or drawing (dimensional tolerances shall be included on the casting drawing), 5.1.2. Grade, 5.1.3. Heat treatment, 5.1.4. Identify wetted surface(s), 5.1.5. Options in the specification, 5.1.6. Whether castings are to be produced using the investment casting process, and 5.1.7. Supplementary req
17、uirements desired, including the standards of acceptance. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 285M/M 285-3 AASHTO 6. PROCESS 6.1. Alloys shall be melted by the electric furnace proces
18、s with or without separate refining, such as argon-oxygen-decarburization (AOD). 7. HEAT TREATMENT 7.1. Castings shall be heat treated in accordance with the requirements in Table 1. Note 2Proper heat treatment of these alloys is usually necessary to enhance corrosion resistance and, in some cases,
19、to meet mechanical properties. Minimum heat-treat temperatures are specified; however, it is sometimes necessary to heat treat at higher temperatures, hold for some minimum time at temperature, and then rapidly cool the castings in order to enhance the corrosion resistance and meet mechanical proper
20、ties. Table 1Heat-Treatment Requirements Grade (UNS) Heat Treatment CF8 (J92600), CG8M (J93000), CF8M (J92900), CF8C (J92710), CF3 (J92500), CF3M (J92800), CG3M (J92999)aHeat to 1040C 1900F minimum, hold for sufficient time to heat casting to temperature, quench in water or rapid cool by other means
21、. CN7M (N08007), CN3MCu (J80020) Heat to 1120C 2050F minimum, hold for sufficient time to heat casting to temperature, quench in water or rapid cool by other means. CN7MS (J94650) Heat to 1150C 2100F minimum, 1180C 2150F maximum, hold for sufficient time (2 h minimum) to heat casting to temperature
22、and quench in water. CN3MN (J94651) Heat to 1150C 2100F minimum, hold for sufficient time to heat casting to temperature, quench in water or cool rapidly by other means. CK3MCuN (J93254) Heat to 1150C 2100F minimum, hold for sufficient time to heat casting to temperature, quench in water or rapid co
23、ol by other means. aFor optimum tensile strength, ductility, and corrosion resistance, the solution annealing temperatures for Grades CF8M, CG8M, and CF3M should be in excess of 1040C 1900F. 8. CHEMICAL REQUIREMENTS 8.1. The materials shall conform with the chemical requirements prescribed in Table
24、2. 9. WORKMANSHIP, FINISH, AND APPEARANCE 9.1. Machined welding ends shall be suitably protected against damage during shipping. 10. REPAIR BY WELDING 10.1. The composition of the deposited weld metal shall be similar to that of the casting except in grade CK3MCuN. In the case of grade CK3MCuN, the
25、composition of the deposited metal shall be similar to that of AWS A5.14 ER NiCrMo-3 (UNS NO6625) or AWS A5.11 E NiCrMo-3 (UNS W86112) when postweld heat treatment is not required, and the composition of the deposited metal shall be either similar to that of the base metal or similar to that of AWS
26、A5.14 ER NiCrMo-3 or AWS A5.11 E NiCrMo-3 when postweld heat treatment is required. 10.1.1. The composition of the deposited weld metal shall be similar to that of the casting except in grade CN3MN. In the case of grade CN3MN, the composition of the deposited weld metal shall be similar to that of A
27、WS A5.14 ER NiCrMo-3 or ER NiCrMo-4 or ER NiCrMo-10 or the 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 285M/M 285-4 AASHTO composition of the deposited weld metal shall be similar to that of
28、AWS A5.11 E NiCrMo-3 or E NiCrMo-4 or E NiCrMo-10 when postweld heat treatment is or is not required. 10.2. Weld repairs shall be considered major in the case of a casting that has leaked on hydrostatic test or when the depth of the cavity after preparation for repair exceeds 20 percent of the actua
29、l wall thickness, or 25 mm 1 in., whichever is smaller, or when the extent of the cavity exceeds approximately 65 cm210 in.2. All other weld repairs shall be considered minor. Major and minor weld repairs shall be subject to the same quality standards as are used to inspect the castings. When method
30、s involving high temperatures are used in the removal of discontinuities, castings shall be preheated to 10C 50F minimum. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.Table 2Chemical Requirements Comp
31、osition, % Grade (UNS) Type Carbon, Max Man- ganese, Max Silicon, Max Phos- phorus, Max Sulfur, Max Chro- mium Nickel Molyb- denum Colum- bium Copper Sele- nium Tungsten, Max Vana- dium, Max Iron, Max Nitrogen CF8 (J92600) 19 Chromium, 9 Nickel 0.08 1.50 2.0 0.04 0.04 18.021.0 8.011.0 CF8M (J92900)
32、19 Chromium, 10 Nickel with Molybdenum 0.08 1.50 2.0 0.04 0.04 18.021.0 9.012.0 2.03.0 CF8C (J92710) 19 Chromium, 10 Nickel with Columbium 0.08 1.50 2.0 0.04 0.04 18.021.0 9.012.0 a CF3 (J92500) 19 Chromium, 9 Nickel 0.03b1.50 2.0 0.04 0.04 17.021.0 8.012.0 CF3M (J92800) 19 Chromium, 10 Nickel with
33、Molybdenum 0.03b1.50 1.50 0.04 0.04 17.021.0 9.013.0 2.03.0 CG3M (J92999) 19 Chromium, 11 Nickel with Molybdenum 0.03 1.50 1.50 0.04 0.04 18.021.0 9.013.0 3.04.0 CG8M (J93000) 19 Chromium, 11 Nickel with Molybdenum 0.08 1.50 1.50 0.04 0.04 18.021.0 9.013.0 3.04.0 CN7M (N08007) 20 Chromium, 29 Nickel
34、 with Copper and Molybdenum 0.07 1.50 1.50 0.04 0.04 19.022.0 27.530.5 2.03.0 3.04.0 CN7MS (J94650) 19 Chromium, 24 Nickel with Copper and Molybdenum 0.07 1.0 2.503.50 0.04 0.03 18.020.0 22.025.0 2.53.0 1.52.0 CN3MN (J94651) 21 Chromium, 24 Nickel with Molybdenum and Nitrogen 0.03 2.00 1.00 0.040 0.
35、010 20.022.0 23.525.5 6.007.00 0.75 max 0.180.26 CK3MCuN (J93254) 20 Chromium, 18 Nickel with Molybdenum and Copper 0.025 1.20 1.00 0.045 0.010 19.520.5 17.519.5 6.07.0 0.051.00 0.1800.240 CN3MCu (J80020) 20 Chromium, 29 Nickel with Copper and Molybdenum 0.03 1.50 1.0 0.030 0.015 19.022.0 27.530.5 2
36、.03.0 3.03.5 a Grade CF8C shall have a columbium content of not less than eight times the carbon content and not more than 1.0 percent. If a columbian-plus-tantalum alloy in the approximate Cb:Ta ratio of 3:1 is used for stabilizing this grade, the total columbium-plus-tantalum content shall not be
37、less than nine times the carbon content and shall not exceed 1.1 percent. b For purposes of determining conformance with this specification, the observed or calculated value for carbon content shall be rounded to the nearest 0.01 percent in accordance with the rounding method of ASTM E29. TS-4hM 285
38、M/M 285-5AASHTO 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 285M/M 285-6 AASHTO 10.3. Castings shall be postweld heat treated in accordance with Table 1 after all major weld repairs and after
39、 those minor weld repairs involving either of the following conditions: (1) welding on a wetted surface, or (2) welding that heats a wetted surface to or above 425C 800F. Note 3The maximum wetted surface temperature of 425C 800F permitted on minor weld repairs without subsequent heat treatment for t
40、he austenitic grades is necessary to avoid sensitization to intergranular corrosion. Minor repairs of this type can be made by using a low heat input (example, 2000 J/mm 50 000 J/in.) welding process or by cooling wetted surfaces with water during welding, or both. Wetted surface temperature measure
41、ment can be accomplished with temperature-indicating crayon or contact pyrometer. 11. REJECTION AND REHEARING 11.1. Samples that represent rejected material shall be preserved for two weeks from the date of transmission of the rejection report. In case of dissatisfaction with the results of the test
42、s, the manufacturer may make claim for a rehearing within that time. 12. PRODUCT MARKING 12.1. Castings shall be marked for material identification with the AASHTO M 285M/M 285 or ASTM A744/A744M specification number and grade symbol; that is, CF8, CN7M, etc. In addition, the manufacturers name or i
43、dentification mark and the pattern number shall be cast or stamped using low-stress stamps on all castings. Small-size castings may be such that marking must be limited consistent with the available area. The marking of heat numbers on individual castings shall be agreed upon by the manufacturer and
44、 the purchaser. Marking shall be in such position as not to injure the usefulness of the casting. 13. KEYWORDS 13.1. Austenitic stainless steel; corrosion; stainless steel; steel castings. SUPPLEMENTARY REQUIREMENTS The following supplementary requirements shall not apply unless specified in the pur
45、chase order. A list of standard supplementary requirements for use at the option of the purchaser is included in ASTM A781/A781M. Those that are ordinarily considered for use with this specification are given below. Others enumerated in ASTM A781/A781M may be used with this specification upon agreem
46、ent between the manufacturer and the purchaser. S2. RADIOGRAPHIC EXAMINATION S3. LIQUID PENETRANT EXAMINATION S5. EXAMINATION OF WELD PREPARATION S6. CERTIFICATION 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applic
47、able law.TS-4h M 285M/M 285-7 AASHTO S7. PRIOR APPROVAL OF MAJOR WELD REPAIRS S21. INTERGRANULAR CORROSION TEST S21.1 An intergranular corrosion test shall be performed in accordance with the appropriate practice for the grade involved, as listed in ASTM A262, or as agreed upon with the purchaser. I
48、ntergranular corrosion tests on stabilized or 0.03 percent carbon maximum grades (CF3, CF3M, CF8C, CG3M, CK3MCuN, and CN3MN) shall be made on sensitized specimens. On all other grades of chromium-nickel steels, intergranular corrosion tests shall be made on specimens representative of the as-shipped
49、 condition. S22. TENSION TEST S22.1 Tensile properties shall be determined from material representing each heat. The bar from which the test specimen is taken shall be heat treated in production furnaces to the same procedure as the casting it represents. The results shall conform to the requirements specified in
