ASTM A982/A982M-10(2020)

Standard Specification for Steel Forgings, Stainless, for Compressor and Turbine Airfoils

ABSTRACT
This specification covers stainless steel forgings for compressor and turbine bucket, blade, and airfoil applications. The stainless steel shall be made by the melting process and either the closed impression die or the open die forging processes may be utilized. Two complete heat treatments, consisting of an austenize, quench, and temper, are permitted. When heat treatment for mechanical properties is followed by straightening, a stress-relieving heat treatment is required. The forgings shall be subjected to tension, impact, hardness, and non-destructive tests. All forgings shall be free of cracks, seams, laps, shrinkage, and similar discontinuities.
SCOPE
1.1 This specification covers stainless steel forgings for compressor and turbine bucket, blade, and airfoil applications.  
1.2 This specification is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable M designation (SI units), the inch-pound units shall apply. The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.3 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: 29-Feb-2020
• ICS: 77.140.85 - Iron and steel forgings
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.06 - Steel Forgings and Billets

Relations

• Replaces: ASTM A982/A982M-10(2015) - Standard Specification for Steel Forgings, Stainless, for Compressor and Turbine Airfoils
• Effective Date: 01-Mar-2020
• Refers: ASTM A275/A275M-23 - Standard Practice for Magnetic Particle Examination of Steel Forgings
• Effective Date: 01-Nov-2023
• Refers: ASTM E562-19e1 - Standard Test Method for Determining Volume Fraction by Systematic Manual Point Count
• Effective Date: 15-Aug-2019
• Refers: ASTM A788/A788M-19 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-May-2019
• Refers: ASTM A788/A788M-18b - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Nov-2018
• Refers: ASTM A788/A788M-18a - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Sep-2018
• Refers: ASTM A788/A788M-18 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Mar-2018
• Refers: ASTM A788/A788M-17a - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Nov-2017
• Refers: ASTM A788/A788M-17 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-May-2017
• Refers: ASTM A788/A788M-16a - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Dec-2016
• Refers: ASTM A788/A788M-15 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-May-2015
• Refers: ASTM A788/A788M-14a - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Oct-2014
• Refers: ASTM A788/A788M-14 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 15-May-2014
• Refers: ASTM A788/A788M-13 - Standard Specification for Steel Forgings, General Requirements
• Effective Date: 01-Nov-2013
• Refers: ASTM A275/A275M-08(2013) - Standard Practice for Magnetic Particle Examination of Steel Forgings
• Effective Date: 01-Apr-2013

Overview

ASTM A982/A982M-10(2020): Standard Specification for Steel Forgings, Stainless, for Compressor and Turbine Airfoils establishes the requirements for stainless steel forgings used in compressor and turbine bucket, blade, and airfoil components. Developed by ASTM International, this standard supports manufacturers and purchasers in the procurement, quality assurance, and traceability of essential rotating and static components within turbomachinery. The document covers materials supplied in both inch-pound and SI units, with clear guidelines on manufacturing, processing, and testing to ensure high performance and safety in demanding applications.

Key Topics

• Material Scope: Specifies various stainless steel grades used for compressor and turbine airfoils, each with defined chemical composition, mechanical properties, and heat treatment requirements.
• Manufacturing Processes: Permits both closed impression die and open die forging methods. The steel may be produced by any ASTM A788/A788M approved melting process unless requirements for secondary melting and refining are invoked by the purchaser.
• Heat Treatment: Requires austenitizing, quenching, and tempering cycles to achieve the necessary mechanical properties. Tables within the standard detail precise temperature ranges for each grade and class.
• Mechanical Properties: Sets rigorous benchmarks for tensile strength, yield strength, elongation, reduction of area, impact, and hardness. Testing is conducted post heat treatment and, if relevant, after a stress-relieving process.
• Testing and Inspection: Mandates tension, impact, and hardness tests, along with non-destructive evaluations to identify surface and internal defects (such as cracks, seams, laps, and shrinkage). Magnetic particle and ultrasonic inspections are included as supplementary requirements when specified.
• Traceability and Certification: Requires comprehensive documentation, including unique lot control, test results, and certification that all forgings comply with ASTM A982/A982M specifications.

Applications

• Aerospace and Power Generation: Fundamental for OEMs and suppliers manufacturing or repairing compressor and turbine airfoils for aircraft engines and power turbines, where material integrity and performance are critical.
• Industrial Gas and Steam Turbines: Ensures the mechanical reliability and corrosion resistance of rotating blades and static vanes exposed to high temperature, pressure, and stress cycles.
• Quality Assurance and Procurement: Provides purchasing agents, engineers, and quality managers with a standard method for ordering, inspecting, and verifying stainless steel forgings for safety-critical applications.
• Design Specification and Compliance: Assists design engineers in selecting appropriate materials and treatments, ensuring compliance with international trade requirements and industry best practice.

Related Standards

• ASTM A788/A788M - General requirements for steel forgings, referenced for baseline requirements on manufacturing, sampling, and testing methods.
• ASTM E112 - Test methods for determining average grain size, important for material property verification.
• ASTM A275/A275M - Practice for magnetic particle examination to detect surface discontinuities.
• ASTM E292 - Procedures for conducting time-for-rupture (stress rupture) notch tension tests.
• ASTM E381 - Macroetch testing guidelines for steel bars, billets, blooms, and forgings, relevant for macrostructure evaluation.

Practical Value

Adhering to ASTM A982/A982M is vital for any organization involved in the manufacture, supply, or maintenance of turbomachinery. The specification assures consistent material quality, mechanical strength, and reliability, while facilitating compliance with international standards and customer requirements. Utilizing this standard helps minimize the risk of premature component failure, supports international trade, and boosts confidence in the supply chain for turbine and compressor airfoil components.

Keywords: ASTM A982/A982M, stainless steel forgings, compressor airfoils, turbine blades, mechanical properties, heat treatment, non-destructive testing, aerospace standards, power generation, material specification, steel forgings for turbines.

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: A982/A982M −10 (Reapproved 2020)
Standard Specification for
Steel Forgings, Stainless, for Compressor and Turbine
Airfoils
This standard is issued under the fixed designationA982/A982M; 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 E562Test Method for Determining Volume Fraction by
Systematic Manual Point Count
1.1 This specification covers stainless steel forgings for
compressor and turbine bucket, blade, and airfoil applications.
3. Ordering Information
1.2 This specification is expressed in both inch-pound units
3.1 In addition to the ordering information required by
and in SI units; however, unless the purchase order or contract
Specification A788/A788M, the purchaser shall include a
specifies the applicable M designation (SI units), the inch-
sketchorwrittendescriptionoftheforgingwiththeinquiryand
pound units shall apply.The values stated in either inch-pound
order.
units or SI units are to be regarded separately as standard.
4. General Requirements
Within the text, the SI units are shown in brackets. The values
stated in each system are not necessarily exact equivalents;
4.1 Materials supplied to this specification shall conform to
therefore, to ensure conformance with the standard, each the requirements of Specification A788/A788M, which out-
system shall be used independently of the other, and values
lines additional ordering information, manufacturing
from the two systems shall not be combined. requirements, testing and retesting methods and procedures,
marking, certification, product analysis variations and addi-
1.3 This international standard was developed in accor-
tional supplementary requirements.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
4.2 If the requirements of this specification are in conflict
Development of International Standards, Guides and Recom-
with the requirements of Specification A788/A788M, the
mendations issued by the World Trade Organization Technical
requirements of this specification shall prevail.
Barriers to Trade (TBT) Committee.
5. Manufacture
2. Referenced Documents
5.1 MeltingProcess—AllmeltingprocessesofSpecification
2.1 ASTM Standards: A788/A788M are permitted unless Supplementary Require-
ment S1 is invoked by the purchaser.
A275/A275MPracticeforMagneticParticleExaminationof
Steel Forgings
5.2 Forging Process—Either the closed impression die or
A788/A788MSpecification for Steel Forgings, General Re-
the open die forging processes may be utilized unless the
quirements
purchaser specifies one or the other.
E112Test Methods for Determining Average Grain Size
5.2.1 Forging Temperature—The maximum part tempera-
E292Test Methods for Conducting Time-for-Rupture Notch
ture during forging shall be 2150°F [1175°C].
Tension Tests of Materials
5.3 HeatTreatment—Heattreatingallforgingsisrequiredin
E381Method of Macroetch Testing Steel Bars, Billets,
accordance with Table 1 to develop the required mechanical
Blooms, and Forgings
properties.
5.3.1 Number of Heat Treatments—Two complete heat
treatments, consisting of an austenitize, quench, and temper,
are permitted. Purchaser approval is required prior to any
This specification is under the jurisdiction ofASTM Committee A01 on Steel,
Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee additional heat treatments.
A01.06 on Steel Forgings and Billets.
5.3.2 Temperature Variation—Heat treating temperatures
Current edition approved March 1, 2020. Published March 2020. Originally
shall be controlled in the range of 625°F [614°C].
published in 1998. Last previous edition approved in 2015 as A982/A982M–10
(2015). DOI: 10.1520/A0982_A0982M–10R20.
5.4 Stress Relief—When heat treatment for mechanical
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
properties is followed by straightening, a stress-relieving heat
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
treatmentisrequiredatatemperaturemeetingtherequirements
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. of Table 1.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A982/A982M − 10 (2020)
TABLE 1 Heat Treatment, °F [°C]
Grade A Grade B Grade C Grade D Grade E Grade F
Classes1&2 Class1 Class1 Class2 Classes1&2 Class1 Class2 Class1
Austenitizing 1725-1775 1600-1750 1825-1875 1725-1875 1875-1925 2075-2125 1725-1775 1875-1925
[940-970] [870-955] [995-1025] [940-1025] [1025-1050] [1135-1165] [940-970] [1025-1050]
Quenching Air or liquid Air or liquid Air or liquid Air or liquid Air or liquid Air or liquid Air or liquid Air or liquid
Single tempering 1050 min 1050 min 1050 min 1050 min 1150 min 1250 min 1100 min .
[565 min] [565 min] [565 min] [565 min] [620 min] [675 min] [595 min]
Double tempering . . . . . . 1025 min 1025 min . . . .
[550 min] [550 min]
Aging . . . . . . . . . . . . . . . . . . . . . 1135-1165
[615-630]
Stress Relieving 1025 min 1025 min 1000 min 1000 min 1100 min 1200 min 1050 min 1100 min
[550 min] [550 min] [540 min] [540 min] [595 min] [650 min] [565 min] [595 min]
5.4.1 QuenchingafterStressRelief—Wateroroilquenching 7.1.1.3 Test Locations—One tension test specimen and one
of stress-relieved forgings is prohibited. set of three impact test specimens shall be machined from the
center portion of the air foil vane section.
6. Chemical Composition
7.1.2 Forging Hardness Testing:
7.1.2.1 Batch Type Furnaces—A minimum of 10% of the
6.1 Thesteelshallconformtotherequirementsforchemical
forgings in each lot shall be hardness tested.
composition prescribed in Table 2.
7.1.2.2 Continuous Type Furnaces—Samples for hardness
7. Mechanical Properties
testing shall be taken from every other tray or push.
7.1 Tension, Impact, and Hardness Tests—All testing shall
8. Nondestructive Examination
be performed after heat treatment and stress relief, as appli-
cable.The test specimens shall meet the requirements of Table
8.1 General Requirements—All forgings shall be free of
3.
cracks, seams, laps, shrinkage, and similar discontinuities.
7.1.1 Number of Tests—A minimum of two forgings from
8.2 NondestructiveTests—Nondestructivetestingandcorre-
each lot shall be randomly selected for longitudinal tensile,
sponding acceptance criteria shall be as specified by the
impact, and hardness testing. Hardness values of the tension
purchaser.
test specimen shall be reported with the tensile data.
7.1.1.1 Lot Size—A lot shall consist of all forgings of the
9. Certification and Reports
same size from one electric furnace heat of steel and heat
9.1 All tests required by this specification shall be made by
treated either in the same charge in either a batch furnace or a
the manufacturer and reported on a certificate of test to the
continuous type furnace.
purchaser. Each test certificate shall include the following
7.1.1.2 Continuous Heat Treating Furnaces—Test forgings
items:
shallbetakenfromeachofthefirstandlastpushortraytoexit
9.1.1 Purchase order number,
the furnace. Additional forgings shall be taken so that the
maximum time between samples is 4 h. 9.1.2 Forging identification number,
TABL
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