ASTM B639-02(2018)
(Specification)Standard Specification for Precipitation Hardening Cobalt-Containing Alloys (UNS R30155 and UNS R30816) Rod, Bar, Forgings, and Forging Stock for High-Temperature Service
Standard Specification for Precipitation Hardening Cobalt-Containing Alloys (UNS R30155 and UNS R30816) Rod, Bar, Forgings, and Forging Stock for High-Temperature Service
ABSTRACT
This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816) rod, bar, forgings, and forging stock for high temperature service. The material shall conform to the required chemical composition for carbon, manganese, silicon, phosphorus, sulfur, chromium, nickel, molybdenum, columbium, tantalum, iron, cobalt, and nitrogen. The materials shall conform to the required tensile and hardness properties such namely tensile strength, yield strength, alongation and Brinell hardness. The alloys shall also conform to the required stress-rupture properties. Dimensions such as diameter, thickness, or width, out-of-round, corners, cut lengths, straightness for cold-worked and hot-worked rod and bar shall be measured.
SCOPE
1.1 This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816)2 rod, bar, forgings, and forging stock for high-temperature service.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
- Status
- Published
- Publication Date
- 31-Oct-2018
- Technical Committee
- B02 - Nonferrous Metals and Alloys
- Drafting Committee
- B02.07 - Refined Nickel and Cobalt and Their Alloys
Relations
- Effective Date
- 01-Nov-2018
- Effective Date
- 01-Jan-2024
- Effective Date
- 15-Jul-2016
- Effective Date
- 01-Feb-2015
- Effective Date
- 01-Jun-2013
- Effective Date
- 01-Dec-2011
- Effective Date
- 01-Jun-2011
- Effective Date
- 01-Oct-2008
- Effective Date
- 01-Mar-2008
- Effective Date
- 15-Nov-2006
- Effective Date
- 15-Sep-2006
- Effective Date
- 01-May-2006
- Effective Date
- 01-May-2006
- Effective Date
- 01-Dec-2004
- Effective Date
- 01-Dec-2003
Overview
ASTM B639-02(2018) is the international standard specification governing precipitation hardening, cobalt-containing alloys (UNS R30155 and UNS R30816) in the form of rod, bar, forgings, and forging stock intended for high-temperature service. Developed and maintained by ASTM International, this standard ensures material integrity, performance consistency, and the mechanical and chemical property requirements essential for demanding environments such as power generation, aerospace, and industrial applications.
The specification addresses the composition, mechanical properties, dimensional tolerances, heat treatment, and testing requirements to guarantee that these alloys perform reliably under extreme conditions.
Key Topics
- Material Scope: Covers hot- and cold-worked precipitation hardening alloys containing cobalt (UNS R30155, UNS R30816) for use as rod, bar, forgings, and forging stock.
- Chemical Composition: Specifies limits for carbon, manganese, silicon, phosphorus, sulfur, chromium, nickel, molybdenum, tungsten, columbium plus tantalum, iron, cobalt, and nitrogen to ensure alloy uniformity and high-temperature capabilities.
- Mechanical Properties: Establishes minimum values for tensile strength, yield strength, elongation, reduction of area, Brinell hardness, and stress-rupture performance, which are critical for service at elevated temperatures.
- Dimensional and Tolerance Requirements: Details permissible variations in diameter, thickness, straightness, and cut lengths to facilitate high-precision manufacturing and assembly.
- Heat Treatment: Recommends solution and precipitation hardening heat treatments to maximize mechanical properties for high-temperature operation.
- Sampling and Testing: Outlines standardized methods for sampling, testing, and certification to verify compliance with ASTM B639-02(2018) requirements.
- Product Marking and Certification: Details marking protocols and the certification process for traceability and assurance of material conformity.
Applications
Alloys specified in ASTM B639-02(2018) are ideal for critical high-temperature service components where resistance to heat, oxidation, and mechanical stress is paramount. Common applications include:
- Aerospace: Turbine engine parts, afterburner components, and structural elements subject to extreme heat and stress.
- Power Generation: Steam and gas turbine components, high-temperature fasteners, and heat exchangers.
- Industrial Processing: Furnace parts, chemically resistant valve stems, and forging dies subjected to cyclical thermal and mechanical loading.
These components benefit from the precipitation hardening characteristics and corrosion resistance of cobalt-containing alloys, which enable safe, reliable operation over long service lives.
Related Standards
Additional standards relevant to the procurement and evaluation of precipitation hardening cobalt alloys include:
- ASTM E8/E8M: Test Methods for Tension Testing of Metallic Materials, referenced for mechanical performance evaluation.
- ASTM E29: Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications, guiding rounding and reporting.
- ASTM E139: Test Methods for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials, critical for high-temperature stress-rupture analysis.
- ASTM E1473: Test Methods for Chemical Analysis of Nickel, Cobalt, and High-Temperature Alloys.
- ASTM B880: Specification for General Requirements for Chemical Check Analysis Limits for Nickel, Nickel Alloys, and Cobalt Alloys.
Organizations selecting materials for high-temperature service should reference ASTM B639-02(2018) and related standards to ensure compliance, safety, and optimal performance across all critical applications involving precipitation hardening cobalt alloys.
Keywords: ASTM B639, precipitation hardening alloys, cobalt-containing alloys, UNS R30155, UNS R30816, high-temperature service, rod, bar, forgings, forging stock, mechanical properties, chemical composition, alloy standards.
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Frequently Asked Questions
ASTM B639-02(2018) is a technical specification published by ASTM International. Its full title is "Standard Specification for Precipitation Hardening Cobalt-Containing Alloys (UNS R30155 and UNS R30816) Rod, Bar, Forgings, and Forging Stock for High-Temperature Service". This standard covers: ABSTRACT This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816) rod, bar, forgings, and forging stock for high temperature service. The material shall conform to the required chemical composition for carbon, manganese, silicon, phosphorus, sulfur, chromium, nickel, molybdenum, columbium, tantalum, iron, cobalt, and nitrogen. The materials shall conform to the required tensile and hardness properties such namely tensile strength, yield strength, alongation and Brinell hardness. The alloys shall also conform to the required stress-rupture properties. Dimensions such as diameter, thickness, or width, out-of-round, corners, cut lengths, straightness for cold-worked and hot-worked rod and bar shall be measured. SCOPE 1.1 This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816)2 rod, bar, forgings, and forging stock for high-temperature service. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ABSTRACT This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816) rod, bar, forgings, and forging stock for high temperature service. The material shall conform to the required chemical composition for carbon, manganese, silicon, phosphorus, sulfur, chromium, nickel, molybdenum, columbium, tantalum, iron, cobalt, and nitrogen. The materials shall conform to the required tensile and hardness properties such namely tensile strength, yield strength, alongation and Brinell hardness. The alloys shall also conform to the required stress-rupture properties. Dimensions such as diameter, thickness, or width, out-of-round, corners, cut lengths, straightness for cold-worked and hot-worked rod and bar shall be measured. SCOPE 1.1 This specification covers hot- and cold-worked precipitation hardenable cobalt-containing alloys (UNS R30155 and UNS R30816)2 rod, bar, forgings, and forging stock for high-temperature service. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ASTM B639-02(2018) is classified under the following ICS (International Classification for Standards) categories: 77.140.60 - Steel bars and rods; 77.140.85 - Iron and steel forgings. The ICS classification helps identify the subject area and facilitates finding related standards.
ASTM B639-02(2018) has the following relationships with other standards: It is inter standard links to ASTM B639-02(2013), ASTM E8/E8M-24, ASTM E8/E8M-16, ASTM E8/E8M-15, ASTM E8/E8M-13, ASTM E8/E8M-11, ASTM E139-11, ASTM E29-08, ASTM B880-03(2008), ASTM E29-06b, ASTM E29-06a, ASTM E29-06, ASTM E139-06, ASTM E29-04, ASTM E1473-03. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
ASTM B639-02(2018) is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:B639 −02(Reapproved 2018)
Standard Specification for
Precipitation Hardening Cobalt-Containing Alloys (UNS
R30155 and UNSR30816) Rod, Bar, Forgings, and Forging
Stock for High-Temperature Service
This standard is issued under the fixed designation B639; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E8/E8MTest Methods for Tension Testing of Metallic Ma-
terials
1.1 This specification covers hot- and cold-worked precipi-
E29Practice for Using Significant Digits in Test Data to
tation hardenable cobalt-containing alloys (UNS R30155 and
2 Determine Conformance with Specifications
UNS R30816) rod, bar, forgings, and forging stock for
E139Test Methods for Conducting Creep, Creep-Rupture,
high-temperature service.
and Stress-Rupture Tests of Metallic Materials
1.2 The values stated in inch-pound units are to be regarded
E1473Test Methods for Chemical Analysis of Nickel, Co-
as standard. The values given in parentheses are mathematical
balt and High-Temperature Alloys
conversions to SI units that are provided for information only
and are not considered standard.
3. Terminology
1.3 This standard does not purport to address all of the
3.1 Definitions of Terms Specific to This Standard:
safety concerns, if any, associated with its use. It is the
3.1.1 bar, n—material of rectangular (flats), hexagonal,
responsibility of the user of this standard to become familiar
octagonal, or square solid section in straight lengths.
with all hazards including those identified in the appropriate
3.1.2 rod, n—material of round solid section furnished in
Safety Data Sheet (SDS) for this product/material as provided
straight lengths.
by the manufacturer, to establish appropriate safety, health,
and environmental practices, and determine the applicability
4. Ordering Information
of regulatory limitations prior to use.
1.4 This international standard was developed in accor-
4.1 It is the responsibility of the purchaser to specify all
dance with internationally recognized principles on standard-
requirements that are necessary for material ordered under this
ization established in the Decision on Principles for the
specification. Examples of such requirements include, but are
Development of International Standards, Guides and Recom-
not limited to, the following:
mendations issued by the World Trade Organization Technical
4.1.1 Alloy Name or UNS Number (see Table 1).
Barriers to Trade (TBT) Committee.
4.1.2 ASTM Designation, including year of issue.
4.1.3 Condition (temper) (Table 4).
2. Referenced Documents
4.1.4 Section—Rod or bar (round, rectangle, square,
2.1 ASTM Standards:
hexagon, octagon).
B880Specification for General Requirements for Chemical
4.1.4.1 Forging (sketch or drawing).
Check Analysis Limits for Nickel, Nickel Alloys and
4.1.5 Dimensions, including length.
Cobalt Alloys
4.1.6 Quantity (mass or number of pieces).
4.1.7 Forging stock—Specify if material is stock for reforg-
ing.
This specification is under the jurisdiction of ASTM Committee B02 on
4.1.8 Finish.
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
B02.07 on Refined Nickel and Cobalt and Their Alloys. 4.1.9 Certification—State if certification or a report of test
Current edition approved Nov. 1, 2018. Published November 2018. Originally
results is required (Section 15).
approved in 1970. Last previous edition approved in 2013 as B639–02 (2013).
4.1.10 Samples for Product (Check) Analysis—Whether
DOI: 10.1520/B0639-02R18.
samplesforproduct(check)analysisshouldbefurnished(9.2).
Designation established in accordance with Practices E527 and SAE J1086.
Practice for Numbering Metals and Alloys (UNS).
4.1.11 Purchaser Inspection—If the purchaser wishes to
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
witness the tests or inspection of material at the place of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
manufacture,thepurchaseordermustsostateindicatingwhich
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. tests or inspections are to be witnessed (Section 13).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B639−02(2018)
TABLE 1 Chemical Requirements
Element Composition Limits, % Composition Limits, %
UNS R30155 (Formerly UNS R30816 (Formerly
Grade 661) Grade 671)
Carbon 0.08 to 0.16 0.32 to 0.42
Manganese 1.00 to 2.00 1.00 to 2.00
Silicon 1.00 max 1.00 max
Phosphorus 0.040 max 0.040 max
Sulfur 0.030 max 0.030 max
Chromium 20.00 to 22.50 19.00 to 21.00
Nickel 19.00 to 21.00 19.00 to 21.00
Molybdenum 2.50 to 3.50 3.50 to 4.50
Tungsten 2.00 to 3.00 3.50 to 4.50
Columbium + tantalum 0.75 to 1.25 3.50 to 4.50
A
Iron remainder 5.00 max
Cobalt 18.50 to 21.00 40.00 min
Nitrogen 0.20 max .
A
Element shall be determined arithmetically by difference.
A
TABLE 2 Tensile and Hardness Requirements
Elongation in 2 in. Reduction Brinell
Tensile Strength, Yield Strength (0.2 %
Alloy Heat Treatment or 50.8 mm or 4 D, of Area, Hardness,
min, psi (MPa) offset), min, psi (MPa)
min, % min, % min
R30155 solution + precipitation harden 110 000 (760) 50 000 (345) 30 30 192
R30816 solution + precipitation harden 130 000 (895) 60 000 (415) 20 20 248
A
The supplier shall demonstrate that the material will meet fully heat-treated properties after full heat treatment in accordance with Table 4.
A
TABLE 3 Stress-Rupture Requirements
Test Temperature, °F Elongation in 2 in. or 50.8
B
Alloy Heat Treatment Stress, psi (MPa) Minimum, h
(°C) mm, or 4D,min,%
R30155 solution + precipitation harden 1350 (732) 24 000 (165) 100 10
R30816 solution + precipitation harden 1350 (732) 38 000 (260) 100 8
A
The supplier shall demonstrate that material will meet fully heat-treated properties after full heat treatment in accordance with Table 4.
B
Test specimens meeting minimum requirements may be overloaded to produce rupture in a reasonable and practical time period.
A
TABLE 4 Heat Treatment
7. Dimensions and Permissible Variations
Recommended Solution
Alloy Precipitation Hardening Treatment
7.1 Diameter, Thickness, or Width—The permissible varia-
Treatment
R30155 2125 to 2175°F (1162 to 1475 to 1525°F (801 to 829°C) tionsfromthespecifieddimensionsofcold-workedrodandbar
1190°C) hold 30 min, hold 4 h, air cool or furnace
shallbeasprescribedinTable5,andofhot-workedrodandbar
minimum, water quench cool
as prescribed in Table 6.
R30816 2130 to 2170°F (1165 to 1390 to 1410°F (754 to 765°C)
1187°C), hold 1 h, water hold 12 h, air cool or furnace 7.1.1 Out-of-Round—Cold-worked and hot-worked rod, all
quench cool
sizes, in straight lengths, shall not be out-of-round by more
A
The purchaser shall designate on the purchase order or inquiry any partial stage
thanonehalfthetotalpermissiblevariationsindiametershown
of heat treatment required on the material to be shipped.
in Table 5 and Table 6, except for hot-worked rod ⁄2 in. (12.7
TABLE 5 Permissible Variations in Diameter or Distance Between
5. Chemical Composition
Parallel Surfaces of Cold-Worked Rod and Bar
5.1 The material shall conform to the chemical composition Permissible Variations from
A
Specified Dimension, in. (mm)
Specified Dimension, in. (mm)
limits specified in Table 1.
+−
5.2 If a product (check) analysis is performed by the
Rods:
purchaser, the material shall conform to the product (check)
1 3
⁄16 to ⁄16 (1.59 to 4.76), excl 0 0.002 (0.051)
3 1
⁄16 to ⁄2 (4.76 to 12.70), excl 0 0.003 (0.076)
analysis variations per Specification B880.
1 15
⁄2 to ⁄16 (12.70 to 23.81), incl 0.001 (0.025) 0.002 (0.051)
15 15
Over ⁄16 to 1 ⁄16 (23.81 to 49.2), 0.0015 (0.038) 0.003 (0.076)
6. Mechanical Requirements
incl
15 1
Over 1 ⁄16 to 2 ⁄2 (49.2 to 63.5), incl 0.002 (0.051) 0.004 (0.102)
6.1 Tensile and Hardness Requirements—The material shall
Bars:
conformtotherequirementsfortensileandhardnessproperties
1 3
⁄16 to ⁄16 (1.59 to 4.76), excl 0 0.002 (0.051)
3 1
in Table 2. ⁄16 to ⁄2 (4.76 to 12.7), excl 0 0.003 (0.076)
A
Dimensions apply to the diameter of rods, to the distance between parallel
6.
...




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