ASTM B637 Standard Specification
Dr. Robert Anderson
Senior Materials Scientist
ASTM B 637 - Standard Specification for Precipitation-Hardening Nickel Alloy Bars, Forgings, and Forging Stock for High-Temperature Service.
Abstract
This standard is issued under the fixed designation B 637; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon ((\epsilon)) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope
1.1 This specification covers hot- and cold-worked precipitation-hardenable nickel alloy rod, bar, forgings, and forging stock for high-temperature service (Table 1).
1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in brackets are for information only.
2. Referenced Documents
2.1 ASTM Standards:
- E 8 Test Methods for Tension Testing of Metallic Materials
- E 29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
- E 139 Test Methods for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials
- E 1473 Test Methods for Chemical Analysis of Nickel, Cobalt, and High-Temperature Alloys
3. Terminology
3.1 Definitions:
3.1.1 bar—material of rectangular (flats), hexagonal, octagonal, or square solid section in straight lengths.
3.1.2 rod—material of round solid section furnished in straight lengths.
4. Ordering Information
4.1 It is the responsibility of the purchaser to specify all requirements that are necessary for the safe and satisfactory performance of material ordered under this specification. Examples of such requirements include, but are not limited to, the following:
4.1.1 Alloy (Table 1).
4.1.2 Condition (temper) (Table 2).
4.1.3 Shape—Rod or bar (round, rectangle, square, hexagon, octagon).
4.1.3.1 Forging (sketch or drawing).
4.1.4 Dimensions, including length.
4.1.5 Quantity (mass or number of pieces).
4.1.6 Forging Stock—Specify if material is stock for reforging.
4.1.7 Finish.
4.1.8 Certification—State if certification is required (Section 15).
4.1.9 Samples for Product (Check) Analysis—Whether samples for product (check) analysis shall be furnished (9.2).
4.1.10 Purchaser Inspection—If the purchaser wishes to witness tests or inspection of material at the place of manufacture, the purchase order must so state indicating which tests or inspections are to be witnessed (Section 13).
5. Chemical Composition
5.1 The material shall conform to the requirements as to chemical composition prescribed in Table 1.
5.2 If a product (check) analysis is performed by the purchaser, the material shall conform to the product (check) analysis variations prescribed in Table 1.
6. Mechanical Properties
6.1 Unless otherwise specified, the material shall be supplied in the solution treated condition, suitable for subsequent age hardening.
6.2 The solution treated material shall be capable of meeting the mechanical property requirements of Table 3, and the stress rupture requirements of Table 4, following the precipitation hardening treatment described in Table 2.
6.3 When the material is to be supplied in the solution treated plus aged condition, the requirements of Table 3 and Table 4 shall apply, with the precipitation hardening treatment of Table 2, or as agreed upon between the purchaser and the manufacturer as part of the purchase contract.
7. Dimensions and Permissible Variations
7.1 Diameter, Thickness, or Width—The permissible variations from the specified dimensions of cold-worked rod and bar shall be as prescribed in Table 5, and of hot-worked rod and bar as prescribed in Table 6.
TABLE 1 Chemical Requirements
| Element | UNS N07252 (Formerly Grade 689) Composition Limits, % | Product (Check) Analysis Variations, under min or over max, of the Specified Limit of Element | UNS N07001 (Formerly Grade 685) Composition Limits, % | Product (Check) Analysis Variations, under min or over max, of the Specified Limit of Element |
|---|---|---|---|---|
| Carbon | 0.10-0.20 | 0.01 | 0.03-0.10 | 0.01 |
| Manganese | 0.50 max | 0.03 | 1.00 max | 0.03 |
| Silicon | 0.50 max | 0.03 | 0.75 max | 0.05 |
| Phosphorus | 0.015 max | 0.005 | 0.030 max | 0.005 |
| Sulfur | 0.015 max | 0.003 | 0.030 max | 0.005 |
| Chromium | 18.00-20.00 | 0.25 | 18.00-21.00 | 0.25 |
| Cobalt | 9.00-11.00 | 0.10 under min, 0.15 over max | 12.00-15.00 | 0.15 |
| Molybdenum | 9.00-10.50 | 0.15 | 3.50-5.00 | 0.10 |
| Titanium | 2.25-2.75 | 0.07 | 2.75-3.25 | 0.07 |
| Aluminum | 0.75-1.25 | 0.10 | 1.20-1.60 | 0.10 |
| Zirconium | ... | ... | 0.02-0.12 | 0.01 under min, 0.02 over max |
| Boron | 0.003-0.01 | 0.002 | 0.003-0.01 | 0.002 |
| Iron | 5.00 max | 0.07 | 2.00 max | 0.05 |
| Copper | ... | ... | 0.50 max | 0.03 |
| Nickel | remainder(^A) | ... | remainder(^A) | ... |
| UNS N07500 (Formerly Grade 684) | UNS N07750 (Formerly Grade 688) | |||
| Carbon | 0.15 max | 0.01 | 0.08 max | 0.01 |
| Manganese | 0.75 max | 0.03 | 1.00 max | 0.03 |
| Silicon | 0.75 max | 0.05 | 0.50 max | 0.03 |
| Phosphorus | 0.015 max | 0.005 | ... | ... |
| Sulfur | 0.015 max | 0.003 | 0.01 max | 0.003 |
| Chromium | 15.00-20.00 | 0.15 under min, 0.25 over max | 14.00-17.00 | 0.15 under min, 0.25 over max |
| Cobalt | 13.00-20.00 | 0.15 under min, 0.20 over max | 1.00 max(^B) | 0.03 |
| Molybdenum | 3.00-5.00 | 0.10 | ... | ... |
| Columbium (Nb) + tantalum | ... | ... | 0.70-1.20 | 0.05 |
| Titanium | 2.50-3.25 | 0.07 | 2.25-2.75 | 0.07 |
| Aluminum | 2.50-3.25 | 0.20 | 0.40-1.00 | 0.05 under min, 0.10 over max |
| Boron | 0.003-0.01 | 0.002 | ... | ... |
| Iron | 4.00-7.00 | 0.07 | 5.00-9.00 | 0.10 |
| Copper | 0.50 max | 0.03 | 0.50 max | 0.03 |
| Nickel | remainder(^A) | ... | remainder(^A) | ... |
| UNS N07718 (Formerly Grade 687) | UNS N07080 (Formerly Grade 686) | |||
| Carbon | 0.08 max | 0.01 | 0.10 max | 0.01 |
| Manganese | 0.35 max | 0.03 | 1.00 max | 0.03 |
| Silicon | 0.35 max | 0.03 | 0.80 max | 0.05 |
| Phosphorus | 0.015 max | 0.005 | 0.025 max | 0.005 |
| Sulfur | 0.015 max | 0.003 | 0.015 max | 0.003 |
| Chromium | 17.00-21.00 | 0.25 | 18.00-21.00 | 0.25 |
| Cobalt | 1.00 max | 0.03 | 0.50 max | 0.03 |
| Molybdenum | 2.80-3.30 | 0.10 | 1.00 max | 0.05 |
| Columbium (Nb) + tantalum | 4.75-5.50 | 0.10 | ... | ... |
| Titanium | 0.65-1.15 | 0.05 | 2.25-2.75 | 0.07 |
| Aluminum | 0.20-0.80 | 0.05 | 1.00-1.80 | 0.10 |
| Boron | 0.006 max<616> | 0.002 | 0.008 max | 0.002 |
| Iron | remainder | 0.07 | 1.00 max | 0.05 |
| Copper | 0.30 max | 0.03 | 0.20 max | 0.03 |
| Nickel | 50.0-55.0 | 0.35 | remainder(^A) | ... |
| UNS N07752 | ||||
| Carbon | 0.05 max | 0.005 | ||
| Manganese | 0.75 max | 0.03 | ||
| Silicon | 0.50 max | 0.03 | ||
| Phosphorus | 0.015 max | 0.005 | ||
| Sulfur | 0.010 max | 0.003 | ||
| Chromium | 19.00-21.00 | 0.25 | ||
| Cobalt | 1.00 max | 0.03 | ||
| Molybdenum | 1.50 max | 0.05 | ||
| Titanium | 2.00-2.50 | 0.07 | ||
| Aluminum | 1.00-1.50 | 0.10 | ||
| Boron | 0.003-0.01 | 0.002 | ||
| Iron | 3.00-6.00 | 0.07 | ||
| Copper | 0.50 max | 0.03 | ||
| Nickel | remainder(^A) | ... |
(^A) The supplier shall demonstrate that the material will meet fully heat-treated properties after full heat treatment in accordance with Table 2.
(^B) Test specimens meeting minimum requirements may be overloaded to produce rupture in a reasonable and practical time period.
TABLE 2 Heat Treatment
| Alloy UNS No. | Solution Treatment Temperature, °F [°C] | Precipitation Heat Treatment Temperature, °F [°C] | Time, h |
|---|---|---|---|
| N07252 | 2150 [1177] | 1850 [1010] | 1 |
| 1550 [843] | 16 | ||
| 1350 [732] | 8 | ||
| N07001 | 2000 [1093] | 1350 [732] | 16 |
| N07500 | 2250 [1232] | 1600 [871] | 24 |
| 1200 [649] | 16 | ||
| N07750 | 1800 [982] | 1350 [732] | 8 |
| 1150 [621] | 8 | ||
| N07718 | 1800 [982] | 1325 [718] | 8 |
| 1150 [621] | 8 | ||
| N07080 | 1975 [1079] | 1290 [699] | 16 |
| N07752 | 2050 [1121] | 1400 [760] | 4 |
| 1200 [649] | 4 |
TABLE 3 Mechanical Property Requirements (Room Temperature)
| Alloy UNS No. | Tensile Strength, min, ksi [MPa] | Yield Strength (0.2% offset), min, ksi [MPa] | Elongation in 4D, min, % | Reduction of Area, min, % |
|---|---|---|---|---|
| N07252 | 180 [1241] | 120 [827] | 15 | 18 |
| N07001 | 150 [1034] | 100 [689] | 15 | 18 |
| N07500 | 180 [1241] | 130 [896] | 10 | 12 |
| N07750 | 120 [827] | 80 [552] | 15 | 18 |
| N07718 | 180 [1241] | 150 [1034] | 12 | 15 |
| N07080 | 180 [1241] | 120 [827] | 15 | 18 |
| N07752 | 180 [1241] | 120 [827] | 12 | 15 |
TABLE 4 Stress-Rupture Requirements
| Alloy UNS No. | Stress, ksi [MPa] | Temperature, °F [°C] | Minimum Rupture Life, h | Minimum Elongation in 4D, % |
|---|---|---|---|---|
| N07252 | 50 [345] | 1350 [732] | 100 | 5 |
| N07001 | 45 [310] | 1200 [649] | 100 | 5 |
| N07500 | 60 [414] | 1200 [649] | 100 | 5 |
| N07750 | 38 [262] | 1200 [649] | 100 | 5 |
| N07718 | 65 [448] | 1200 [649] | 100 | 5 |
| N07080 | 60 [414] | 1200 [649] | 100 | 5 |
| N07752 | 60 [414] | 1200 [649] | 100 | 5 |
TABLE 5 Permissible Variations in Diameter or Distance Between Parallel Surfaces of Cold-Worked Rods and Bars
| Specified Dimension, in. [mm](^A) | Permissible Variations from Specified Dimension, in. [mm] | |
|---|---|---|
| Plus | Minus | |
| Rods: | ||
| 1/16 to 3/16 [1.59 to 4.76], excl | 0 | 0.002 [0.051] |
| 3/16 to 1/8 [4.76 to 12.70], excl | 0 | 0.003 [0.076] |
| 1/2 to 15/16 [12.70 to 23.81], incl | 0.001 [0.025] | 0.002 [0.051] |
| Over 15/16 to 1 15/16 [23.81 to 49.2], incl | 0.0015 [0.038] | 0.003 [0.076] |
| Over 1 15/16 to 2 1/2 [49.2 to 63.5], incl | 0.002 [0.051] | 0.004 [0.102] |
| Bars: | ||
| 1/16 to 3/16 [1.59 to 4.76], excl | 0 | 0.002 [0.051] |
| 3/16 to 1/8 [4.76 to 12.7], excl | 0 | 0.003 [0.076] |
(^A) Dimensions apply to the diameter of rods, to the distance between parallel surfaces of hexagonal, octagonal, and square bar, and separately to width and thickness of rectangular bar.
TABLE 6 Permissible Variations in Diameter or Distance Between Parallel Surfaces of Hot-Worked Rods and Bars
| Specified Dimension, in. [mm](^A) | Permissible Variations from Specified Dimension, in. [mm] | |
|---|---|---|
| + | - | |
| Rod and bar, hot-finished: | ||
| 1 [25.4] and under | 0.016 [0.406] | 0.016 [0.406] |
| Over 1 to 2 [25.4 to 50.8], incl | 0.031 [0.787] | 0.016 [0.406] |
| Over 2 to 4 [50.8 to 101.6], incl | 0.047 [1.19] | 0.031 [0.787] |
| Over 4 [101.6] | 0.125 [3.18] | 0.063 [1.60] |
| Rod, hot-finished and rough-turned or ground: | ||
| Under 1 [25] | 0.005 [0.13] | 0.005 [0.13] |
| 1 [25] and over | 0.031 [0.79] | 0 |
(^A) Dimensions apply to the diameter of rods, to the distance between parallel surfaces of hexagonal, octagonal, and square bar, and separately to width and thickness of rectangular bar.
11. Testing and Chemical Analysis
11.1.3 Forging stock test specimens shall be taken from a forged-down coupon or a sample taken directly from stock.
11.2 Forgings:
11.2.1 The tension test specimen representing each lot shall be taken from a forging or from a test prolongation.
11.2.2 The axis of the specimen shall be located at any point midway between the center and the surface of solid forgings and at any point midway between the inner and outer surfaces of the wall of hollow forgings, and shall be parallel to the direction of greatest metal flow.
11.2.3 The specimens shall be the largest possible round-type shown in Test Methods E 8.
11.3 Stress-rupture specimens shall be the same as tension specimens except modified as necessary for stress-rupture testing in accordance with Practice E 139.
12. Test Methods
12.1 Determine the chemical composition and mechanical and other properties of the material as enumerated in this specification, in case of disagreement, in accordance with the following methods:
| Test | ASTM Designation |
|---|---|
| Chemical analysis | E 1473 |
| Tension | E 8 |
| Rounding procedure | E 29 |
| Stress-rupture | E 139 |
12.2 For purposes of determining compliance with the specified limits for requirements of the properties listed in the following table, an observed value or a calculated value shall be rounded in accordance with the rounding method of Practice E 29.
| Test | Rounded Unit for Observed Or Calculated Value |
|---|---|
| Chemical composition, tolerances (when expressed in decimals), and hardness | Nearest unit in the last right-hand place of figures of the specified limit. If two choices are possible, as when the digits dropped are exactly a 5 or a 5 followed only by zeros, choose the one ending in an even digit, with zero defined as an even digit. |
| Tensile strength and yield strength | Nearest 1000 psi [6.9 MPa] |
| Elongation | Nearest 1% |
| Rupture life | 1 h |
13. Inspection
13.1 Inspection of the material shall be made as agreed upon between the manufacturer and the purchaser as part of the purchase contract.
14. Rejection and Rehearing
14.1 Material, tested by the purchaser, that fails to conform to the requirements of this specification may be rejected. Rejection should be reported to the producer or supplier promptly and in writing. In case of dissatisfaction with the results of the test, the producer or supplier may make claim for a rehearing.
15. Certification
15.1 When specified in the purchase order or contract, a producer's or supplier's certification shall be furnished to the purchaser that the material was manufactured, sampled, tested, and inspected in accordance with this specification and has been found to meet the requirements. When specified in the purchase order or contract, a report of the test results shall be furnished.
16. Product Marking
16.1 Each bundle or shipping container shall be marked with the name of the material; condition (temper); this specification number; the size; gross, tare, and net weight; consignor and consignee address; contract or order number; or such other information as may be defined in the contract or order.
17. Keywords
17.1 N07252; N07001; N07500; N07750; N07718; N07080; N07752; bar; billet