ASTM F2581-12(2017)

Standard Specification for Wrought Nitrogen Strengthened 11Manganese-17Chromium-3Molybdenum Low-Nickel Stainless Steel Alloy Bar and Wire for Surgical Implants (UNS S29225)

ABSTRACT
This specification covers the chemical, mechanical, and metallurgical requirements for wrought nitrogen strengthened 11manganese-17chromium-3molybdenum (UNS S29225) low-nickel stainless steel alloy bars and wires for surgical implants. The alloys shall be furnished in the annealed or cold-worked condition, and finished cold-drawn, pickled, ground, ground and polished, or as specified by the purchaser. Mechanical properties to which the alloys shall conform are ultimate tensile strength, yield strength, elongation, and reduction of area.
SCOPE
1.1 This specification covers the chemical, mechanical, and metallurgical requirements for wrought nitrogen strengthened 11manganese-17chromium-3molybdenum low-nickel stainless steel alloy bar and wire for 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 and health 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-Aug-2017
• ICS: 11.040.40 - Implants for surgery, prosthetics and orthotics
• ICS: 77.140.20 - Stainless steels
• Technical Committee: F04 - Medical and Surgical Materials and Devices
• Drafting Committee: F04.12 - Metallurgical Materials

Relations

• 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 E407-23 - Standard Practice for Microetching Metals and Alloys
• Effective Date: 01-Nov-2023
• Refers: ASTM E45-18a(2023) - Standard Test Methods for Determining the Inclusion Content of Steel
• 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 F138-19 - 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 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 F1314-18 - Standard Specification for Wrought Nitrogen Strengthened 22 Chromium–13 Nickel–5 Manganese–2.5 Molybdenum Stainless Steel Alloy Bar and Wire for Surgical Implants (UNS S20910)
• Effective Date: 01-Feb-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 F2581-12(2017) is an international standard specification developed by ASTM International, outlining the requirements for wrought, nitrogen-strengthened, 11manganese-17chromium-3molybdenum low-nickel stainless steel alloy bar and wire for surgical implants (UNS S29225). This standard focuses on the chemical, mechanical, and metallurgical properties essential for the safe and effective use of stainless steel alloy materials in critical surgical implant applications. The specification supports both SI and inch-pound units, ensuring global applicability. Compliance with ASTM F2581-12(2017) helps medical device manufacturers and material suppliers to produce high-quality surgical implant components that meet stringent industry requirements.

Key Topics

• Material Composition: Specifies precise chemical composition limits for essential elements such as manganese, chromium, molybdenum, nitrogen, and low levels of nickel, ensuring optimal corrosion resistance and mechanical strength.
• Mechanical Properties: Covers requirements for ultimate tensile strength, yield strength, elongation, and reduction of area, supporting a high level of reliability and performance in surgical use.
• Metallurgical Requirements: Ensures a fine-grained, fully austenitic structure, free from delta ferrite, chi, and sigma phases, and verified inclusion content for consistent material properties.
• Delivery Conditions & Finishes: Allows the material to be furnished in annealed or cold-worked conditions, with various finish options such as cold-drawn, pickled, ground, or ground and polished, as specified by purchasers.
• Testing and Inspection: References essential ASTM and ISO test methods for chemical analysis, hardness, tensile testing, and microstructure evaluation. Includes guidelines for ultrasonic inspection and intergranular corrosion testing.
• Certification and Traceability: Requires material certification and full reporting of test results, supporting quality assurance and regulatory compliance for surgical implant materials.

Applications

• Surgical Implants: The primary application of ASTM F2581-12(2017) alloy bar and wire is in the manufacturing of surgical implants, where biocompatibility, mechanical strength, and corrosion resistance are critical.
• Medical Devices: Used as starting material for forging and fabricating various medical device components that require enhanced performance in demanding environments.
• Orthopedic Applications: Frequently selected for orthopedic devices due to its high strength and favorable biocompatibility profile.
• MRI-Environments: The alloy’s nonmagnetic properties, achieved by excluding magnetic phases like delta ferrite, make it suitable for use in medical devices intended for patients undergoing magnetic resonance imaging (MRI).

Related Standards

• ASTM F138: Specification for wrought 18chromium-14nickel-2.5molybdenum stainless steel bar and wire for surgical implants (UNS S31673).
• ASTM F1314: Specification for wrought nitrogen-strengthened 22chromium-13nickel-5manganese-2.5molybdenum stainless steel alloy bar and wire for surgical implants.
• ASTM F1586: Specification for wrought nitrogen-strengthened 21chromium-10nickel-3manganese-2.5molybdenum stainless steel alloy bar for surgical implants.
• ISO 6892: Metallic materials – Tensile testing at ambient temperature.
• ISO 9001: Quality management systems – Requirements.
• ASTM A262: Practices for detecting susceptibility to intergranular attack in austenitic stainless steels.
• ASTM E8/E8M, E10, E18, E45, E112: Various test methods referenced for evaluating mechanical properties and microstructure.

Practical Value

Aligning with ASTM F2581-12(2017) ensures that materials used in surgical implants meet high-quality, internationally recognized standards for safety, consistency, and performance. This contributes to improved patient outcomes, greater trust in medical devices, and streamlined regulatory approval processes. For manufacturers and suppliers, adherence to this standard strengthens product credibility and market acceptance in the medical and surgical device industry.

Keywords: ASTM F2581-12, surgical implants, stainless steel alloy, nitrogen-strengthened, low-nickel, medical devices, UNS S29225, biocompatibility, corrosion resistance, orthopedic materials, international standard.

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: F2581 − 12 (Reapproved 2017)
Standard Specification for
Wrought Nitrogen Strengthened 11Manganese-17Chromium-
3Molybdenum Low-Nickel Stainless Steel Alloy Bar and Wire
for Surgical Implants (UNS S29225)
This standard is issued under the fixed designation F2581; 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.
1. Scope* A751 Test Methods and Practices for Chemical Analysis of
Steel Products
1.1 This specification covers the chemical, mechanical, and
E8/E8M Test Methods for Tension Testing of Metallic Ma-
metallurgical requirements for wrought nitrogen strengthened
terials
11manganese-17chromium-3molybdenum low-nickel stainless
E10 Test Method for Brinell Hardness of Metallic Materials
steel alloy bar and wire for surgical implants.
E18 Test 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
E29 Practice for Using Significant Digits in Test Data to
each system are not necessarily exact equivalents; therefore, to
Determine Conformance with Specifications
ensure conformance with the standard, each system shall be
E45 Test Methods for Determining the Inclusion Content of
used independently of the other, and values from the two
Steel
systems shall not be combined.
E112 Test 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, and Other Similar Iron,
responsibility of the user of this standard to establish appro-
Nickel, and Cobalt Alloys
priate safety, health, and environmental practices and deter- E407 Practice for Microetching Metals and Alloys
mine the applicability of regulatory limitations prior to use.
F138 Specification for Wrought 18Chromium-14Nickel-
1.4 This international standard was developed in accor- 2.5Molybdenum Stainless Steel Bar and Wire for Surgical
dance with internationally recognized principles on standard-
Implants (UNS S31673)
ization established in the Decision on Principles for the
F746 Test Method for Pitting or Crevice Corrosion of
Development of International Standards, Guides and Recom-
Metallic Surgical Implant Materials
mendations issued by the World Trade Organization Technical
F748 Practice for Selecting Generic Biological Test Methods
Barriers to Trade (TBT) Committee.
for Materials and Devices
F1314 Specification for Wrought Nitrogen Strengthened 22
2. Referenced Documents
Chromium–13 Nickel–5 Manganese–2.5 Molybdenum
2.1 ASTM Standards: Stainless Steel Alloy Bar and Wire for Surgical Implants
A262 Practices for Detecting Susceptibility to Intergranular (UNS S20910)
Attack in Austenitic Stainless Steels F1586 Specification for Wrought Nitrogen Strengthened
A484/A484M Specification for General Requirements for 21Chromium—10Nickel—3Manganese—
Stainless Steel Bars, Billets, and Forgings 2.5Molybdenum Stainless Steel Alloy Bar for Surgical
A555/A555M Specification for General Requirements for Implants (UNS S31675)
Stainless Steel Wire and Wire Rods IEEE/ASTM SI 10 American National Standard for Metric
Practice
2.2 Aerospace Material Specification:
This specification is under the jurisdiction of ASTM Committee F04 on
Medical and Surgical Materials and Devices and is the direct responsibility of
AMS 2248 Chemical Check Analysis Limits, Corrosion and
Subcommittee F04.12 on Metallurgical Materials.
Heat Resistant Steels and Alloys, Maraging and Other
Current edition approved Sept. 1, 2017. Published September 2017. Originally
Highly-Alloyed Steels, and Iron Alloys
approved in 2007. Last previous edition approved in 2012 as F2581 – 12. DOI:
10.1520/F2581-12R17.
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 Available from Society of Automotive Engineers (SAE), 400 Commonwealth
the ASTM website. Dr., Warrendale, PA 15096-0001, http://www.sae.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
F2581 − 12 (2017)
TABLE 1 Chemical Composition
AMS 2630 Inspection, Ultrasonic Product over 0.5 Inch
(12.7 mm) Thick Element Composition, % (mass/mass)
Carbon 0.15 to 0.25
2.3 ISO Standard:
Manganese 9.50 to 12.50
ISO 6892 Metallic Materials Tensile Testing at Ambient
Phosphorus 0.020 max
Temperature Sulfur 0.010 max
Silicon 0.2 to 0.6
ISO 9001 Quality Management Systems—Requirements
Chromium 16.50 to 18.00
Nickel 0.05 max
3. Terminology
Molybdenum 2.70 to 3.70
Nitrogen 0.45 to 0.55
3.1 Definitions of Terms Specific to This Standard:
Copper 0.25 max
3.1.1 bar—round, rectangular, or other complex shaped A
Iron balance
product delivered straightened and cut to defined lengths, with
A
Approximately equal to the difference of 100 % and the sum percentage of the
2 2
a maximum cross-sectional area of 16 in. [103 cm ].
other specified elements. The percentage of iron difference is not required to be
reported.
3.1.2 fine wire—wire with diameter or major dimension less
than 0.063 in. [1.6 mm].
3.1.3 forging bar—bar as described in 3.1.1 used for pro-
duction of forgings, may be furnished in the hot-rolled and
6.1.1 Requirements for the major and minor elemental
descaled condition.
constituents are listed in Table 1. Also listed are important
3.1.4 lot—the total number of mill products produced from
residual elements. Analysis for elements not listed in Table 1 is
the same melt heat under the same conditions at essentially the not required to verify compliance with this specification.
same time.
6.1.2 Methods and practices relating to chemical analysis
required by this specification shall be in accordance with Test
3.1.5 wire—rounds, rectangular, or other complex shaped
Methods A751.
product produced and delivered in coils.
6.1.3 For reference purposes, Test Methods E354 shall
4. Ordering Information
apply.
4.1 Inquiries and orders for material under this specification
6.2 Product Analysis—The product analysis is either for the
shall include the following information:
purpose of verifying the composition of a heat or lot or to
4.1.1 Quantity;
determine variations in the composition within the heat.
4.1.2 ASTM designation and date of issue;
6.2.1 Acceptance or rejection of a heat or lot of material
4.1.3 Mechanical properties;
may be made by the purchaser on the basis of this product
4.1.4 Form;
analysis.
4.1.5 Applicable dimensions including size, thickness,
6.2.2 Product analysis tolerances do not broaden the speci-
width, and length (exact, random, or multiples) or drawing
fied heat analysis requirements but cover variations between
number;
laboratories in the measurement of chemical content. Product
4.1.6 Tolerances—Unless otherwise specified by the
analysis limits shall be as specified in Table 2.
purchaser, tolerances must meet the requirements of Specifi-
cations A484/A484M and A555/A555M, as applicable;
7. Metallurgical Requirements
4.1.7 Condition (see 5.1);
7.1 The material shall contain no delta ferrite, chi, or sigma
4.1.8 Finish (see 5.2);
phases when it is examined metallographically at 100× mag-
4.1.9 Special tests, if any; and
nification in accordance with Practice E407.
4.1.10 Other requirements.
5. Materials and Manufacture
A
TABLE 2 Product Analysis Tolerances
5.1 Condition—Bar and wire shall be furnished, as
Permissible Variation
specified, in the annealed or cold-worked condition. Bar used
Under the Minimum
Element
for the production of forgings may be furnished in the hot
Limit or Over the
B
Maximum Limit, % (mass/mass)
worked and descaled condition, as agreed upon between the
Carbon 0.01
purchaser and supplier.
C
Manganese 0.20
Phosphorus 0.005
5.2 Finish—Types of finish available in bar and wire are
Sulfur 0.005
cold-drawn, pickled, ground, ground and polished, shaved, or
Silicon 0.05
as specified by the purchaser. Chromium 0.25
Nickel 0.03
Molybdenum 0.05
6. Chemical Requirements
C
Nitrogen 0.05
6.1 The supplier’s heat analysis shall conform to the chemi- Copper 0.03
A
cal requirements prescribed in Table 1. The supplier shall not
Refer to AMS 2248 for chemical check analysis limits (except nitrogen).
B
For elements in which only a maximum percentage is indicated, the “under
ship material that is outside the limits specified in Table 1.
minimum limit” is not applicable.
C
The specified range for this element is not covered by AMS 2248 and has been
Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
established through industrial practice.
4th Floor, New York, NY 10036, http://www.ansi.org.
F2581 − 12 (2017)
7.2 The microcleanliness of the steel, as determined by Test 9. Ultrasonic Inspection
Method E45, Method A, on representative billet or bar samples
9.1 All centerless ground or peeled and polished round bar
from the heat shall not exceed the following:
≥ 0.375 in. [9.5 mm] in nominal diameter shall be ultrasoni-
cally inspected at final diameter according to AMS 2630, Class
Inclusion D (Globular
A (Sulphide) B (Alumina) C (Silicate)
A1. Equivalent test methods may be substituted when agreed
Type oxide)
upon by the purchaser and supplier.
Thin 1.5 1.5 1.5 1.5
Heavy 1.0 1.0 1.0 1.0 NOTE 1—AMS 2630 specifies a minimum size limit of 0.50 in. [12.7
mm]. F04.12 subcommittee has intentionally specified the use of AMS
2630 below 0.50 in. [12.7 mm] based on the experience of users and
8. Mechanical Properties
producers on the committee. There is disagreement in the industry as to
whether AMS 2632, which does apply to sizes under 0.50 in. [12.7 mm],
8.1 Tensile Properties:
applies to solid round bar.
8.1.1 Tensile properties shall be determined in accordance
with Test Methods E8/E8M.
10. Dimensions and Permissible Variations
8.1.2 The mechanical properties of test specimens shall
conform to the requirements specified in Table 3. 10.1 Units of Measure:
8.1.3 The level of mechanical properties for material in 10.1.1 Selection—This specification requires that the pur-
other conditions shall be specified in the purchase order. chaser selects the units (SI or inch-pound) to be used for
product certification. In the absence of a stated selection of
8.2 Hardness:
units on the purchase order, this selection may be expressed by
8.2.1 Hardness values shall be determined in accordance
the purchaser in several alternate forms listed in order of
with Test Method E10 or Test Methods E18.
precedence.
8.2.2 When desired, hardness limits may be specified by the
10.1.1.1 If the purchaser and supplier have a history of
purchaser. Hardness determinations shall be made on a product
using specific units, these units shall continue to be certified
cross section, midway between the center and surface, if the
until expressly changed by the purchaser.
cross section is adequate.
10.1.1.2 In the absence of historic precedence, if the units
8.3 Number of Tests:
used to define the product on the purchaser’s purchase order
8.3.1 Perform tension testing per Test Methods E8/E8M.
(PO), specification, and engineering drawing are consistent,
Should any of the test specimens not meet the specified these units shall be used by the supplier for product certifica-
requirements, test two additional test pieces representative of
tion.
the same lot, in the same manner, for each failed test piece. The
10.1.1.3 If the purchaser’s selection of units is unclear, the
lot shall be considered in compliance only if all additional test
units of measure shall be agreed upon between the purchaser
pieces meet the specified requirements.
and supplier.
8.3.2 Tensile test results for which any specimen fractures
10.1.2 Conversion of Units—If the supplier’s test equipment
outside the gauge length shall be considered acceptable, if both
does not report in the selected units, the test equipment units
the elongation and reduction of area meet the minimum
may be converted to the selected units for certification pur-
requirements specified. Refer to subsections 7.11.4 and 7.11.5
poses. Accurate arithmetic conversion and proper use of
of Test Meth
...