ASTM F138-19

Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)

ABSTRACT
This specification covers the requirements for wrought 18chromium-14nickel-2.5molybdenum stainless steel bar and wire used for the manufacture of surgical implants. Bar and wire shall be furnished, as specified, in the hot-worked, annealed, cold -worked, or extra hard condition. Fine wire shall be furnished, as specified, in the cold-drawn condition. Types of finish available for bar and wire products are cold-drawn, pickled, ground, and ground and polished. On the other hand, types of finish available for fine wire products are cold-drawn, ground, and ground and polished. The heat analysis shall conform to the requirements as to chemical composition specified and the material shall contain no delta ferrite, chi, or sigma phases when it is examined by metallography. Different tests shall be performed in order to determine the following mechanical properties of the wire and bar: ultimate tensile strength, yield strength, elongation, and Brinell hardness.
SCOPE
1.1 This specification covers the chemical, mechanical, and metallurgical requirements for wrought 18chromium-14nickel-2.5molybdenum stainless steel bar and wire used for the manufacture of surgical implants.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the 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 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: 30-Nov-2019
• ICS: 11.040.40 - Implants for surgery, prosthetics and orthotics
• Technical Committee: F04 - Medical and Surgical Materials and Devices
• Drafting Committee: F04.12 - Metallurgical Materials

Relations

• Replaces: ASTM F138-13a - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Dec-2019
• Refers: ASTM F1350-24 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Surgical Fixation Wire (UNS S31673)
• Effective Date: 15-Mar-2024
• Refers: ASTM A484/A484M-24 - Standard Specification for General Requirements for Stainless Steel Bars, Billets, Shapes, and Forgings
• Effective Date: 01-Jan-2024
• Refers: ASTM E8/E8M-24 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM E45-18a(2023) - Standard Test Methods for Determining the Inclusion Content of Steel
• Effective Date: 01-Nov-2023
• Refers: ASTM E407-23 - Standard Practice for Microetching Metals and Alloys
• Effective Date: 01-Nov-2023
• Refers: ASTM A484/A484M-23a - Standard Specification for General Requirements for Stainless Steel Bars, Billets, Shapes, and Forgings
• Effective Date: 01-Sep-2023
• Refers: ASTM A484/A484M-23 - Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
• Effective Date: 01-Mar-2023
• Refers: ASTM A484/A484M-20a - Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
• Effective Date: 05-May-2020
• Refers: ASTM A484/A484M-19 - Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
• Effective Date: 01-Sep-2019
• Refers: ASTM A484/A484M-18a - Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
• Effective Date: 01-Nov-2018
• Refers: ASTM E18-18 - Standard Test Methods for Rockwell Hardness of Metallic Materials
• Effective Date: 01-Jul-2018
• Refers: ASTM A484/A484M-18 - Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
• Effective Date: 01-Jan-2018
• Refers: ASTM E18-17 - Standard Test Methods for Rockwell Hardness of Metallic Materials
• Effective Date: 01-Jul-2017
• Refers: ASTM E8/E8M-16 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 15-Jul-2016

Overview

ASTM F138-19 is the internationally recognized standard specification for wrought 18Chromium-14Nickel-2.5Molybdenum stainless steel bar and wire for use in surgical implants, classified as UNS S31673. Published by ASTM International, this standard defines the chemical, mechanical, and metallurgical requirements of stainless steel materials used to manufacture implants placed in the human body.

Developed under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices, ASTM F138-19 ensures that stainless steel bar and wire used for surgical implants demonstrate consistent quality, high corrosion resistance, and proven biocompatibility. This standard is widely referenced in medical manufacturing, regulatory submissions, and international trade, supporting the safety and effectiveness of medical devices globally.

Key Topics

• Material Forms and Conditions

  • The standard covers bar, wire, and fine wire products furnished in hot-worked, annealed, cold-worked, or extra hard conditions.
  • Fine wire is specifically supplied in cold-drawn condition.

• Surface Finishes

  • Options include cold-drawn, pickled, ground, and ground and polished finishes for bar and wire.
  • Fine wire finishes include cold-drawn, ground, or ground and polished.

• Chemical Composition and Purity

  • Strict requirements for chemical composition, with limits on elements such as carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, molybdenum, nitrogen, copper, cobalt, and iron.
  • Prohibition of delta ferrite, chi, or sigma phases to ensure optimal corrosion resistance.

• Mechanical Properties

  • Mandatory evaluation of ultimate tensile strength, yield strength, elongation, and Brinell hardness.
  • Mechanical property values differ depending on the bar or wire condition and dimension.

• Test Methods and Quality Assurance

  • Compliance with referenced ASTM, ISO, and Aerospace Material Standards for chemical analysis, tensile and hardness testing, microstructural evaluation, and ultrasonic inspection.
  • Requirements for quality management systems (ISO 9001, ISO 13485).

• Ordering and Certification

  • Guidance for required ordering information including quantity, material form, mechanical properties, surface finish, and testing requirements.
  • Supplier certification and test reporting are mandatory.

Applications

ASTM F138-19 stainless steel is intended for manufacturing a wide range of surgical implants and medical devices, particularly where high strength, durability, and corrosion resistance are essential. Common applications include:

• Orthopedic implants such as bone plates, screws, pins, and nails
• Cardiovascular devices including suture wires and temporary pacing wires
• Dental implants and fixation systems
• General medical and surgical instruments exposed to the human body

The specification supports reliable selection, processing, and quality control of stainless steel materials used in critical healthcare applications, contributing to patient safety and regulatory compliance in the medical device industry.

Related Standards

• ASTM A484/A484M: General requirements for stainless steel bars, billets, and forgings
• ASTM A555/A555M: General requirements for stainless steel wire and wire rods
• ISO 5832-1: Implants for surgery – Metallic materials – Wrought stainless steel
• ISO 6892: Metallic materials – Tensile testing
• ISO 9001 / ISO 13485: Quality management systems for general and medical device industries
• ASTM F1350: Specification for stainless steel surgical fixation wire (UNS S31673)

Practical Value

By adhering to ASTM F138-19, manufacturers ensure their implantable stainless steel products meet global regulatory expectations for biocompatibility and mechanical performance. The standard guides procurement, production, and quality assurance activities, serving as a benchmark for material certification, device design, and clinical safety in the field of surgical implants and medical devices.

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:F138 −19
Standard Specification for
Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless
Steel Bar and Wire for Surgical Implants (UNS S31673)
ThisstandardisissuedunderthefixeddesignationF138;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* A751Test Methods, Practices, and Terminology for Chemi-
cal Analysis of Steel Products
1.1 This specification covers the chemical, mechanical, and
E8/E8MTest Methods for Tension Testing of Metallic Ma-
metallurgicalrequirementsforwrought18chromium-14nickel-
terials
2.5molybdenum stainless steel bar and wire used for the
E10Test Method for Brinell Hardness of Metallic Materials
manufacture of surgical implants.
E18Test Methods for Rockwell Hardness of Metallic Ma-
1.2 The values stated in either SI units or inch-pound units
terials
are to be regarded separately as standard. The values stated in
E29Practice for Using Significant Digits in Test Data to
each system may not be exact equivalents; therefore, each
Determine Conformance with Specifications
system shall be used independently of the other. Combining
E45Test Methods for Determining the Inclusion Content of
values from the two systems may result in non-conformance
Steel
with the standard.
E112Test Methods for Determining Average Grain Size
1.3 This standard does not purport to address all of the
E354 Test Methods for Chemical Analysis of High-
safety concerns, if any, associated with its use. It is the
Temperature,Electrical,Magnetic,andOtherSimilarIron,
responsibility of the user of this standard to establish appro-
Nickel, and Cobalt Alloys
priate safety, health, and environmental practices and deter-
E407Practice for Microetching Metals and Alloys
mine the applicability of regulatory limitations prior to use.
F981Practice for Assessment of Compatibility of Biomate-
1.4 This international standard was developed in accor-
rials for Surgical Implants with Respect to Effect of
dance with internationally recognized principles on standard-
Materials on Muscle and Insertion into Bone
ization established in the Decision on Principles for the
F1350Specification for Wrought 18Chromium-14Nickel-
Development of International Standards, Guides and Recom-
2.5Molybdenum Stainless Steel Surgical Fixation Wire
mendations issued by the World Trade Organization Technical
(UNS S31673)
Barriers to Trade (TBT) Committee.
IEEE/ASTM SI 10American National Standard for Metric
Practice
2. Referenced Documents
2.2 Aerospace Material Standard:
2.1 ASTM Standards:
AMS 2630Inspection, Ultrasonic Product Over 0.5 inch
A262Practices for Detecting Susceptibility to Intergranular
(12.7 mm) Thick
Attack in Austenitic Stainless Steels
AMS 2632Ultrasonic Inspection of Thin Materials
A484/A484MSpecification for General Requirements for
2.3 ISO Standards:
Stainless Steel Bars, Billets, and Forgings
ISO 5832–1Implants for Surgery—Metallic Materials—
A555/A555MSpecification for General Requirements for
Part 1:Wrought Stainless Steel
Stainless Steel Wire and Wire Rods
ISO 6892Metallic Materials—Tensile Testing
ISO 9001Quality Management Systems—Requirements
This specification is under the jurisdiction of ASTM Committee F04 on
ISO 13485 Medical Devices—Quality Management
Medical and Surgical Materials and Devices and is the direct responsibility of
Systems—Requirements For Regulatory Purposes
Subcommittee F04.12 on Metallurgical Materials.
Current edition approved Dec. 1, 2019. Published February 2020. Originally
approved in 1971. Last previous edition approved in 2013 as F138–13a. DOI:
10.1520/F0138-19.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or AvailablefromSAEInternational(SAE),400CommonwealthDr.,Warrendale,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM PA 15096-0001, http://aerospace.sae.org.
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
*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
F138−19
3. Terminology 6.1.1 Barandwireshallbefurnished,asspecified,inthehot
worked, annealed, cold worked, or extra hard condition (see
3.1 Definitions of Terms Specific to This Standard:
Table 1).
3.1.1 bar, n—round, rectangular, or other complex shaped
6.1.2 Fine wire shall be furnished, as specified, in the cold
product delivered straightened and cut to defined lengths, with
2 2 drawn condition (see Table 2).
a maximum cross-sectional area of 103 cm [16 in. ].
6.2 Finish:
3.1.2 fine wire, n—wire as described in 3.1.5, less than 1.60
6.2.1 Types of finish available for bar and wire products are
mm [0.063 in.] in diameter or thickness.
cold drawn, pickled, ground, ground and polished, or as
3.1.3 forging bar, n—bar as described in 3.1.1, used for the
specified in the purchase order.
production of forgings, may be furnished in the hot worked
6.2.2 Types of finish available for fine wire products are
condition.
descaled or pickled, abrasive-blasted, cold drawn, ground,
3.1.4 lot, n—the total number of mill products produced
ground and polished, or as specified in the purchase order.
from the same melt heat under the same conditions at essen-
tially the same time.
7. Chemical Requirements
3.1.5 wire, n—round, rectangular, or other complex shaped
7.1 Thesupplier’sheatanalysisshallconformtothechemi-
product produced and delivered in coils, spools, or other
cal requirements prescribed in Table 3. The supplier shall not
packaging as specified.
shipmaterialwithchemistryoutsidetherequirementsspecified
in Table 3.
4. General Requirements for Delivery
7.1.1 Requirements for the major and minor elemental
4.1 In addition to the requirements of this specification, all
constituents are listed in Table 3. Also listed are important
requirements of the current editions of Specifications A484/
residualelements.AnalysisforelementsnotlistedinTable3is
A484M and A555/A555M shall apply.
not required to verify compliance with this specification.
4.2 In the case where a conflict exists between this specifi- 7.1.2 All commercial metals may contain small amounts of
elements other than those which are specified. It is neither
cation and those listed in 2.1, 2.2, and 2.3, this specification
shall take precedence. practical nor necessary to specify limits for unspecified ele-
mentsthatcanbepresent.Theproducerispermittedtoanalyze
5. Ordering Information
for unspecified elements and is permitted to report such
analyses. The presence of an unspecified element and the
5.1 Inquiriesandordersformaterialunderthisspecification
reportingofananalysisforthatelementshallnotbeabasisfor
shall include the following information:
rejection unless previously agreed to between purchaser and
5.1.1 Quantity (weight or number of pieces);
supplier.
5.1.2 ASTM designation and date of issue;
7.1.3 Intentional elemental additions other than those speci-
5.1.3 Form (bar, wire, fine wire);
fied in Table 3 are not permitted.
5.1.4 Condition (see 6.1);
7.1.4 Methods and practices relating to chemical analysis
5.1.5 Mechanical properties (if applicable, for special con-
required by this specification shall be in accordance with Test
ditions);
Methods, Practices, and Terminology A751.
5.1.6 Finish (see 6.2);
5.1.7 Applicable dimensions including size, thickness,
7.2 Product Analysis—Product analysis tolerances do not
width, and length (exact, random, or multiples) or drawing
broaden the specified heat analysis requirements, but cover
number;
variations between laboratories in the measurement of chemi-
5.1.8 Special tests, if any; and
cal content. The supplier shall not ship material that is outside
5.1.9 Other requirements.
the limits specified in Table 3.
7.2.1 The product analysis is either for the purpose of
6. Materials and Manufacture
verifying the composition of a heat or manufacturing lot or to
6.1 Condition: determine variations in the composition within the heat.
TABLE 1 Mechanical Requirements, Bar and Wire
B
Ultimate Tensile
Brinell
A
Yield Strength (0.2 %
Elongation
Condition Diameter or Thickness, mm. [in] Strength, min, MPa Hardness, max,
min, %
offset), min, MPa [psi]
HB
[psi]
C
Hot worked all . . . 250
Annealed 1.60 and over [0.063] 490 [71 000] 190 [27 500] 40 . . .
Cold worked 1.60 to 38.1 [0.063 to 1.500] 860 [125 000] 690 [100 000] 12 . . .
Extra-hard 1.60 to 6.35 [0.063 to 0.250] 1350 [196 000] . . . . . . . . .
A
Elongation of material 1.6 mm [0.063 in.] or greater in diameter (D) or width (W) shall be measured using a gauge length of 50 mm [2 in.] or 4D or 4W perTest Methods
E8/E8M.Thegaugelengthshallbereportedwiththetestresults.Alternatively,agaugelengthcorrespondingtoE8MorISO6892(5.65timesthesquarerootofSo,where
So is the original cross-sectional area) may be used when agreed upon between the supplier and purchaser.
B
29-kN [3000-kgf] load.
C
Typically supplied as hot rolled bar for forging applications.
F138−19
A
TABLE 2 Mechanical Requirements, Fine Wire
C
Elongation in 254 mm [10
Ultimate Tensile Strength, MPa
B
Condition Diameter, mm [in.]
[psi]
in.], min, %
860 to 1035
Cold drawn under 1.60 [0.063] 5
[125 000 to 150 000]
A
Annealed fine wire requirements are covered in Specification F1350.
B
Recommended crosshead speed for cold drawn fine wire is 2.0 mm/s [5 in./min].
C
Cold drawn wire may be ordered to tensile strengths up to 2070 MPa [300 000 psi] with lower elongation as determined by the purchaser and supplier.
TABLE 3 Chemical Requirements, Heat Analysis
8.2 The microcleanliness of the steel as determined by
Composition, % Method A of Test Methods E45, except using Plate I-r, on
Element
(mass/mass)
representative billet or bar samples from the heat shall not
Carbon 0.030 max
exceed the following:
Manganese 2.00 max
Phosphorous 0.025 max Inclusion A B C D
Type (Sulfide) (Alumina) (Silicate) (Globular
Sulfur 0.010 max
Silicon 0.75 max Oxides)
Thin 1.5 1.5 1.5 1.5
Chromium 17.00 to 19.00
Heavy 1.0 1.0 1.0 1.0
Nickel 13.00 to 15.00
Molybdenum 2.25 to 3.00
Nitrogen 0.10 max
9. Mechanical Properties
Copper 0.50 max
Cobalt <0.10
9.1 Tensile Properties:
A
Iron balance
9.1.1 Tensile properties shall be determined in accordance
Composition Index=%Cr+3.3×%Mo 26.0min
with Test Methods E8/E8M.
A
The percentage of iron content by difference is not required to be determined or
certified.
9.1.2 Material shall conform to the appropriate require-
ments as to mechanical properties specified in Table 1 and
Table 2.
9.1.3 The level of mechanical properties for material in
7.2.2 Acceptance or rejection of a heat or lot of material conditions other than those included in Table 1 and Table 2,
may be made by the purchaser on the basis of this product
shall be specified in the purchase order.
analysis.
9.1.4 Bar and wire in the cold worked condition can be
7.2.3 Product analysis outside the tolerance limits allowed
supplied to a higher tensile strength and corresponding lower
in Table 4 are cause for rejection of the product. A referee
elongation as specified on the purchase order.
analysismaybeusedifagreeduponbysupplierandpurchaser.
9.1.5 Fine wire in the cold drawn condition can be supplied
7.2.4 Methods and practices relating to chemical analysis
toahighertensilestrengthandcorrespondinglowerelongation
required by this specification shall be in accordance with Test
as specified on the purchase order.
Methods E354.
9.2 Hardness:
9.2.1 Hardness values shall be determined in accordance
8. Metallurgical Requirements
with Test Method E10 or E18.
8.1 The material shall exhibit no delta ferrite, chi, or sigma
9.2.2 Whendesired,hardnesslimitsmaybespecifiedbythe
phases when it is examined metallographically at 100× mag-
purchaser. Hardness determinations shall be made on the
nification when etched in accordance with Practice E407.
product cross section, midway between the center and surface,
if the cross section is adequate.
9.2.3 Hardnessvaluesareforinformationonlyandshallnot
A
TABLE 4 Product Analysis Tolerance
be used as a basis for rejection.
Tolerance Under the
Minimum or Over the
9.3 Number of Tests:
Element
Maximum Limit, %
9.3.1 Performatleastonetensiontestfromeachlot.Should
B
(mass/mass)
any of the test pieces not meet the specified requirements, test
Carbon 0.005
two additional test pieces representative of the
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F138 − 13a F138 − 19
Standard Specification for
Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless
Steel Bar and Wire for Surgical Implants (UNS S31673)
This standard is issued under the fixed designation F138; 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 (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This specification covers the chemical, mechanical, and metallurgical requirements for wrought 18chromium-14nickel-
2.5molybdenum stainless steel bar and wire used for the manufacture of surgical implants.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system aremay not necessarilybe exact equivalents; therefore, to ensure conformance with the standard, each system shall be used
independently of the other, andother. Combining values from the two systems shall not be combined.may result in
non-conformance with the 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 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.
2. Referenced Documents
2.1 ASTM Standards:
A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
A484/A484M Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
A555/A555M Specification for General Requirements for Stainless Steel Wire and Wire Rods
A751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products
E8/E8M Test Methods for Tension Testing of Metallic Materials
E10 Test Method for Brinell Hardness of Metallic Materials
E18 Test Methods for Rockwell Hardness of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E45 Test Methods for Determining the Inclusion Content of Steel
E112 Test Methods for Determining Average Grain Size
E354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron, Nickel, and
Cobalt Alloys
E407 Practice for Microetching Metals and Alloys
F981 Practice for Assessment of Compatibility of Biomaterials for Surgical Implants with Respect to Effect of Materials on
Muscle and Insertion into Bone
F1350 Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Surgical Fixation Wire (UNS S31673)
IEEE/ASTM SI 10 American National Standard for Metric Practice
This specification is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of Subcommittee
F04.12 on Metallurgical Materials.
Current edition approved Oct. 1, 2013Dec. 1, 2019. Published November 2013February 2020. Originally approved in 1971. Last previous edition approved in 2013 as
F138 – 13.F138 – 13a. DOI: 10.1520/F0138-13A.10.1520/F0138-19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*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
F138 − 19
2.2 Aerospace Material Standard:
AMS 2630 Inspection, Ultrasonic Product Over 0.5 inch (12.7 mm) Thick
AMS 2632 Ultrasonic Inspection of Thin Materials
2.3 ISO Standards:
ISO 5832–1 Implants for Surgery—Metallic Materials—Part 1:Wrought Stainless Steel
ISO 6892 Metallic Materials—Tensile Testing
ISO 9001 Quality Management Systems—Requirements
ISO 13485 Medical Devices—Quality Management Systems—Requirements For Regulatory Purposes
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 bar, n—rounds, flats, or other shapes from 0.1875 in. [4.76 mm] to 4 in. [101.60 mm] in diameter or thickness. (Other
sizesround, rectangular, or other complex shaped product delivered straightened and cut to defined lengths, with a maximum
2 2
cross-sectional area of 103 cm and shapes [16 in. by special order.) ].
3.1.2 fine wire, n—wire as described in 3.1.5, less than 0.063 in. [1.60 mm]1.60 mm [0.063 in.] in diameter or thickness.
3.1.3 forging bar, n—bar as described in 3.1.1, used for the production of forgings, may be furnished in the hot worked
condition.
3.1.4 lot, n—the total number of mill products produced from the same melt heat under the same conditions at essentially the
same time.
3.1.5 wire, n—rounds, flats or other shapes less than 0.1875 in. [4.76 mm] in diameter or thickness. round, rectangular, or other
complex shaped product produced and delivered in coils, spools, or other packaging as specified.
4. General Requirements for Delivery
4.1 In addition to the requirements of this specification, all requirements of the current editions of Specifications A484/A484M
and A555/A555M shall apply.
4.2 In the case where a conflict exists between this specification and those listed in 2.1 and 2.32.1, 2.2, and 2.3, this specification
shall take precedence.
5. Ordering Information
5.1 Inquiries and orders for material under this specification shall include the following information:
5.1.1 Quantity (weight or number of pieces);
5.1.2 ASTM designation and date of issue;
5.1.3 Form (bar, wire, fine wire);
5.1.4 Condition (see 6.1);
5.1.5 Mechanical properties (if applicable, for special conditions);
5.1.6 Finish (see 6.2);
5.1.7 Applicable dimensions including size, thickness, width, and length (exact, random, or multiples) or drawing number;
5.1.8 Special tests, if any; and
5.1.9 Other requirements.
6. Materials and Manufacture
6.1 Condition:
6.1.1 Bar and wire shall be furnished, as specified, in the hot worked, annealed, cold worked, or extra hard condition (see Table
1).
6.1.2 Fine wire shall be furnished, as specified, in the cold drawn condition (see Table 2).
6.2 Finish:
6.2.1 Types of finish available for bar and wire products are cold drawn, pickled, ground, ground and polished, or as specified
in the purchase order.
6.2.2 Types of finish available for fine wire products are descaled or pickled, abrasive-blasted, cold drawn, ground, ground and
polished, or as specified in the purchase order.
7. Chemical Requirements
7.1 The supplier’s heat analysis shall conform to the requirements as to chemical composition specifiedchemical requirements
prescribed in Table 3. The supplier shall not ship material with chemistry outside the requirements specified in Table 3.
Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http://aerospace.sae.org.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
F138 − 19
TABLE 1 Mechanical Requirements, Bar and Wire
A B
Ultimate Tensile
Elongation in Brinell
Yield Strength (0.2 %
Condition Diameter or Thickness, in. [mm] Strength, min, psi 4D or Hardness, max,
offset), min, psi [MPa]
4W,min, % HB
[MPa]
C
Hot worked all . . . 250
Annealed 0.063 and over [1.60] 71 000 [490] 27 500 [190] 40 .
Cold worked 0.063 to 1.500 [1.60 to 38.1] 125 000 [860] 100 000 [690] 12 .
Extra-hard 0.063 to 0.250 [1.60 to 6.35] 196 000 [1350] . . .
TABLE 1 Mechanical Requirements, Bar and Wire
B
Ultimate Tensile
Brinell
A
Yield Strength (0.2 % Elongation
Condition Diameter or Thickness, mm. [in] Strength, min, MPa Hardness, max,
min, %
offset), min, MPa [psi]
HB
[psi]
C
Hot worked all . . . . . . . . . 250
Annealed 1.60 and over [0.063] 490 [71 000] 190 [27 500] 40 . . .
Cold worked 1.60 to 38.1 [0.063 to 1.500] 860 [125 000] 690 [100 000] 12 . . .
Extra-hard 1.60 to 6.35 [0.063 to 0.250] 1350 [196 000] . . . . . . . . .
A
The gage Elongation of material 1.6 mm [0.063 in.] or greater in diameter (D) or width (Wlength must be reported with the test results. ) shall be measured using a gauge
length of 50 mm [2 in.] or 4D = 4 × diameter;or 4W = 4 × width. Alternatively, a gage length corresponding to per Test Methods E8/E8M or ISO 6892 may be used when
agreed upon between supplier and purchaser. . The gauge length shall be reported with the test results. Alternatively, a gauge length corresponding to E 8M or ISO 6892
(5.65 times the square root of So, where So is the original cross sectional area). cross-sectional area) may be used when agreed upon between the supplier and purchaser.
B
29-kN 29-kN [3000-kgf] load.
C
Typically supplied as hot rolled bar for forging applications.
A
TABLE 2 Mechanical Requirements, Fine Wire
C
Elongation in 10 in. [254
B Ultimate Tensile Strength, psi
Condition Diameter, in. [mm]
[MPa] mm], min, %
under 0.063 125 000 to 150 000
Cold drawn 5
[1.60] [860 to 1035]
A
TABLE 2 Mechanical Requirements, Fine Wire
C
Elongation in 254 mm [10
Ultimate Tensile Strength, MPa
B
Condition Diameter, mm [in.]
[psi] in.], min, %
under 1.60 860 to 1035
Cold drawn 5
[0.063] [125 000 to 150 000]
A
Annealed fine wire requirements are covered in Specification F1350.
B
Recommended crosshead speed for cold drawn fine wire is 5 in./min [2.0 mm/s].2.0 mm/s [5 in./min].
C
Cold drawn wire may be ordered to tensile strengths up to 300 000 psi [2070 MPa]2070 MPa [300 000 psi] with lower elongation as determined by the purchaser and
supplier.
7.1.1 The compositional requirement shall meet the following:
% Cr13.3 3% Mo $ 26.0 (1)
7.1.1 Requirements for the major and minor elemental constituents are listed in Table 3. Also listed are important residual
elements. Analysis for elements not listed in Table 3 is not required to certifyverify compliance with this specification.
7.1.2 All commercial metals may contain small amounts of elements other than those which are specified. It is neither practical
nor necessary to specify limits for unspecified elements that can be present. The producer is permitted to analyze for unspecified
elements and is permitted to report such analyses. The presence of an unspecified element and the reporting of an analysis for that
element shall not be a basis for rejection unless previously agreed to between purchaser and supplier.
7.1.3 Intentional elemental additions other than those specified in Table 3 are not permitted.
7.1.4 Methods and practices relating to chemical analysis required by this specification shall be in accordance with Test
Methods, Practices, and Terminology A751.
7.2 Product Analysis—Product analysis tolerances do not broaden the specified heat analysis requirements, but cover variations
between laboratories in the measurement of chemical content. The supplier shall not ship material that is outside the limits specified
in Table 3. Product analysis limits shall be as specified in Table 4.
7.2.1 The product analysis is either for the purpose of verifying the composition of a heat or manufacturing lot or to determine
variations in the composition within the heat.
7.2.2 Acceptance or rejection of a heat or lot of material may be made by the purchaser on the basis of this product analysis.
7.2.3 Product analysis outside the tolerance limits allowed in Table 4 are cause for rejection of the product. A referee analysis
may be used if agreed upon by supplier and purchaser.
7.2.4 Methods and practices relating to chemical analysis required by this specification shall be in accordance with Test Methods
E354.
F138 − 19
TABLE 3 Chemical Requirements, Heat Analysis
Composition, %
Element
(mass/mass)
Carbon 0.030 max
Manganese 2.00 max
Phosphorous 0.025 max
Sulfur 0.010 max
Silicon 0.75 max
A
Chromium 17.00 to 19.00
Nickel 13.00 to 15.00
A
Molybdenum 2.25 to 3.00
Nitrogen 0.10 max
Copper 0.50 max
B
Iron balance
TABLE 3 Chemical Requirements, Heat Analysis
Composition, %
Element
(mass/mass)
Carbon 0.030 max
Manganese 2.00 max
Phosphorous 0.025 max
Sulfur 0.010 max
Silicon 0.75 max
Chromium 17.00 to 19.00
Nickel 13.00 to 15.00
Molybdenum 2.25 to 3.00
Nitrogen 0.10 max
Copper 0.50 max
Cobalt <0.10
A
Iron balance
Composition Index = % Cr + 3.3 × % Mo 26.0 min
A
The compositional requirement shall meet the following:
% Cr + 3.3 × % Mo $ 26.0.
A
The percentage of iron content by difference is not required to be determined or
certified.
A
TABLE 4 Product Analysis Tolerance
Tolerance Under the
Minimum or Over the
Element
Maximum Limit, %
B
(mass/mass)
Carbon 0.005
Manganese 0.04
Phosphorous 0.005
Sulfur 0.005
Silicon 0.05
Chromium 0.20
Nickel 0.15
Molybdenum 0.10
Nitrogen 0.01
Copper 0.03
Cobalt 0.01
A
Refer to Specification These limits conform to Specifications A484/A484M and
A555/A555M.
B
Under minimum limit not applicable for elements where only a maximum
percentage is indicated.
8. Metallurgical Requirements
8.1 The material shall exhibit no delta ferrite, chi, or sigma phases when it is examined metallographically at 100×
magnification when etched in accordance with Practice E407.
8.2 The microcleanliness of the steel as determined by Method A of Test Methods E45, except using Plate I-r, on representative
billet or bar samples from the heat shall not exceed the following:
Inclusion A B C D
Type (Sulfide) (Alumina) (Silicate) (Globular
Oxides)
Thin 1.5 1.5 1.5 1.5
Heavy 1.0 1.0 1.0 1.0
F138 − 19
9. Mechanical Properties
9.1 Tensile Properties:
9.1.1 Tensile properties shall be determined in accordance with Test Methods E8/E8M.
9.1.2 Material shall conform to the appropriate requirements as to mechanical properties specified in Table 1 and Table 2.
9.1.3 The level of mechanical properties for material in conditions other than those included in Table 1 and Table 2, shall be
specified in the purchase order.
9.1.4 Bar and wire in the cold worked condition can be supplied to a higher tensile strength and corresponding lower elongation
as specified on the purchase order.
9.1.5 Fine wire in the cold drawn condition can be supplied to a higher tensile
...