ASTM F138-97

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Designation: F 138 – 97
Standard Specification for
Wrought 18 Chromium-14 Nickel-2.5 Molybdenum Stainless
Steel Bar and Wire for Surgical Implants (UNS S31673)
This standard is issued under the fixed designation F 138; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 2.3 ASQ Standard:
C1 Specification of General Requirements for a Quality
1.1 This specification covers the requirements for wrought
Program
18 chromium-14 nickel-2.5 molybdenum stainless steel bar
and wire used for the manufacture of surgical implants.
3. General Requirements for Delivery
1.2 The values stated in inch-pound units are to be regarded
3.1 In addition to the requirements of this specification, all
as the standard. The SI units given in parentheses are for
requirements of the current editions of Specifications A 484/
information only.
A 484M and A 555/A 555M shall apply.
2. Referenced Documents 3.2 In the case where a conflict exists between this specifi-
cation and those listed in 2.1 and 2.2, this specification shall
2.1 ASTM Standards:
take precedence.
A 262 Practices for Detecting Susceptibility to Intergranu-
lar Attack in Austenitic Stainless Steels
4. Ordering Information
A 484/A 484M Specification for General Requirements for
2 4.1 Inquiries and orders for material under this specification
Stainless Steel Bars, Billets, and Forgings
shall include the following information:
A 555/A 555M Specification for General Requirements for
2 4.1.1 Quantity (weight or number of pieces),
Stainless Steel Wire and Wire Rods
4.1.2 ASTM designation,
A 751 Test Methods, Practices, and Terminology for
2 4.1.3 Form (bar, wire, fine wire),
Chemical Analysis of Steel Products
4.1.4 Condition (see 5.1),
E 8/E 8M Test Methods for Tension Testing of Metallic
3 4.1.5 Mechanical properties (if applicable, for special con-
Materials
ditions),
E45 Test Methods for Determining the Inclusion Content
3 4.1.6 Finish (see 5.2),
of Steel
3 4.1.7 Applicable dimensions including size, thickness,
E112 Test Methods for Determining Average Grain Size
width,andlength(exact,randomormultiples)orprintnumber,
F 981 Practice for Assessment of Compatibility of Bioma-
and
terials for Surgical Implants with Respect to Effect of
4 4.1.8 Special requirements.
Materials in Muscle and Bone
F 1350 Specification for Stainless Steel Surgical Fixation
5. Materials and Manufacture
Wire
5.1 Condition:
2.2 ISO Standards:
5.1.1 Bar and wire shall be furnished, as specified, in the
ISO 5832–1 Implants for Surgery—Metallic Materials—
5 hot-worked, annealed, cold -worked, or extra hard condition
Part 1:Wrought Stainless Steel
5 (see Table 1).
ISO 6892 Metallic Materials—Tensile Testing
5.1.2 Fine wire shall be furnished, as specified, in the
cold-drawn condition (see Table 2).
5.2 Finish:
This specification is under the jurisdiction of ASTM Committee F-14 on
5.2.1 Types of finish available for bar and wire products are
Medical and Surgical Materials and Devices and is the direct responsibility of
Subcommittee F04.12 on Metallurgical Materials.
cold-drawn, pickled, ground, ground and polished, or as
Current edition approved June 10, 1997. Published November 1997. Originally
specified in the purchase order.
published as F 138 – 71. Last previous edition F 138 – 92.
Annual Book of ASTM Standards, Vol 01.03.
Annual Book of ASTM Standards, Vol 03.01.
Annual Book of ASTM Standards, Vol 13.01.
5 6
Available from American National Standards Instititute, 1430 Broadway, New Available fromAmerican Society for Quality Control, 161 W. WisconsinAve.,
York, NY 10018. Milwaukee, WI 53203.
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F138–97
TABLE 1 Mechanical Requirements, Wire and Bar
B
Ultimate Tensile Brinell
A
Yield Strength (0.2 % Elongation in
Condition Diameter or Thickness, in. (mm) Strength, min, psi Hardness, max,
offset), min, psi (MPa) 4Dor 4W,min, %
(MPa) HB
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) . . .
A
4D =4 3 diameter; 4W =4 3 width. Alternatively, a gage length corresponding to ISO 6892 may be used when agreed upon between supplier and purchaser.
B
29-kN (3000-kgf) load.
C
Typically supplied as hot-rolled bar for forging applications.
A
TABLE 2 Mechanical Requirements, Fine Wire
C
Ultimate Tensile Strength, psi Elongation in 10 in. (254
B
Condition Diameter, in. (mm)
(MPa) mm), min, %
Cold-drawn under 0.063 125 000 to 150 000 5
(1.60) (860 to 1035)
A
Annealed fine wire requirements are covered in Specification F 1350.
B
Recommended crosshead speed for cold-drawn fine wire is 5 in./min (2.0 mm/s).
C
Cold-drawn wire may be ordered to tensile strengths up to 300 000 psi (2070 MPa) with lower elongation as determined by customer and supplier.
A
TABLE 4 Product Analysis Tolerance
5.2.2 Types of finish available for fine wire products are
Tolerance Under the
cold-drawn, ground, ground and polished, or as specified in the
Element Minimum or Over the
purchase order. B
Maximum Limit
Carbon 0.005
6. Chemical Composition
Manganese 0.04
Phosphorous 0.005
6.1 The heat analysis shall conform to the requirements as
Sulfur 0.005
to chemical composition specified in Table 3.
Silicon 0.05
6.1.1 The pitting resistance equivalent (PRE) shall meet the
Chromium 0.20
Nickel 0.15
following:
Molybdenum 0.10
%Cr 1 3.3 3%Mo$ 26 (1)
Nitrogen 0.01
Copper 0.03
6.1.2 Requirements for the major and minor elemental
A
Refer to Specification A 555/A 555M.
constituents are listed in Table 3. Also listed are important
B
Under minimum limit not applicable for elements where only a minimum
residual elements.Analysis for elements not listed inTable 3 is
percentage is indicated.
not required to certify compliance with this specification.
6.2 Product Analysis—Product analysis tolerances do not
6.2.2 Acceptance or rejection of a heat or lot of material
broaden the specified heat analysis requirements, but cover
may be made by the purchaser on the basis of this check
variations between laboratories in the measurement of chemi-
analysis.
cal content. The manufacturer shall not ship material that is
6.3 Methods and practices relating to chemical analysis
outside the limits specified in Table 3. Product analysis limits
required by this specification shall be in accordance with Test
shall be as specified in Table 4.
Methods, Practices, and Terminology A 751.
6.2.1 The product analysis is either for the purpose of
verifying the composition of a heat or lot or to determine 7. Metallurgical Requirements
variations in the composition within the heat.
7.1 The material shall contain no free ferrite phase when it
is examined metallographically at 1003 magnification.
7.2 The microcleanliness of the steel as determined by
TABLE 3 Chemical Requirements, Heat Analysis
Method A of Test Methods E45, except using Plate I-r, on
Element Composition, %
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
Sulfur 0.010 max
Type (Sulfide) (Alumina) (Silicate) (Globular Ox-
Silicon 0.75 max
ides)
A
Chromium 17.00 to 19.
...