ASTM F2886-10

Standard Specification for Metal Injection Molded Cobalt-28Chromium-6Molybdenum Components for Surgical Implant Applications

ABSTRACT
This specification covers chemical, mechanical, and metallurgical general requirements for metal injection molded (MIM) cobalt-28chromium-6molybddenum components to be used in manufacturing surgical implants. In this specification, the MIM components covered may have been densified beyond their as-sintered density by post-sinter processing. For the chemical requirements, the components supplied in this specification must conform in accordance to the chemical requirements specified herein in Table 1. The product analysis tolerances must also conform to the product tolerances presented in Table 2. The specification also enumerates the mechanical requirements for MIM components wherein the tensile properties of the MIM must conform to the mechanical properties in Table 3. The microstructural requirements and specimen preparation shall be in accordance with Guide E3 and Practice E407.
SCOPE
1.1 This specification covers the chemical, mechanical, and metallurgical requirements for metal injection molded (MIM) cobalt-28chromium-6molybdenum components to be used in the manufacture of surgical implants
1.2 The MIM components covered by this specification may have been densified beyond their as-sintered density by post-sinter processing.
1.3 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.

General Information

• Status: Historical
• Publication Date: 30-Nov-2010
• 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

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F2886 −10
Standard Specification for
Metal Injection Molded Cobalt-28Chromium-6Molybdenum
Components for Surgical Implant Applications
This standard is issued under the fixed designation F2886; 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 F75 Specification for Cobalt-28 Chromium-6 Molybdenum
Alloy Castings and Casting Alloy for Surgical Implants
1.1 This specification covers the chemical, mechanical, and
(UNS R30075)
metallurgical requirements for metal injection molded (MIM)
F601 Practice for Fluorescent Penetrant Inspection of Me-
cobalt-28chromium-6molybdenum components to be used in
tallic Surgical Implants
the manufacture of surgical implants
F629 Practice for Radiography of Cast Metallic Surgical
1.2 TheMIMcomponentscoveredbythisspecificationmay
Implants
have been densified beyond their as-sintered density by post-
F1537 Specification for Wrought Cobalt-28Chromium-
sinter processing.
6Molybdenum Alloys for Surgical Implants (UNS
R31537, UNS R31538, and UNS R31539)
1.3 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in SI 10 American National Standard for Use of the Interna-
tional System of Units (SI): The Modern Metric System
each system may not be exact equivalents; therefore, each
system shall be used independently of the other. Combining
2.2 ISO Standards:
values from the two systems may result in non-conformance
ISO 6892 Metallic Materials Tensile Testing at Ambient
with the standard.
Temperature
ISO 9001 Quality Management Systems—Requirements
2. Referenced Documents
2.3 AMS Standards:
2.1 ASTM Standards:
AMS 2269 Chemical CheckAnalysis Limits, Nickel, Nickel
B243 Terminology of Powder Metallurgy
Alloys and Cobalt Alloys
B311 Test Method for Density of Powder Metallurgy (PM)
AMS 2248 Chemical CheckAnalysis Limits, Corrosion and
Materials Containing Less Than Two Percent Porosity
Heat Resistant Steels and Alloys, Maraging and Other
B923 Test Method for Metal Powder Skeletal Density by
Highly-Alloyed Steels, and Iron Alloys
Helium or Nitrogen Pycnometry
2.4 MPIF Standards:
E3 Guide for Preparation of Metallographic Specimens
MPIFStandard10 DeterminationoftheTensilePropertiesof
E8/E8M Test Methods for Tension Testing of Metallic Ma-
Powder Metallurgy Materials
terials
MPIF Standard 42 Determination of Density of Compacted
E29 Practice for Using Significant Digits in Test Data to
or Sintered Powder Metallurgy Products
Determine Conformance with Specifications
MPIF Standard 50 Preparing and Evaluating Metal Injection
E165 Practice for Liquid Penetrant Examination for General
Molded Sintered/Heat Treated Tension Specimens
Industry
MPIF Standard 63 Density Determinations of MIM Compo-
E354 Test Methods for Chemical Analysis of High-
nents (Gas Pycnometry)
Temperature,Electrical,Magnetic,andOtherSimilarIron,
MPIF Standard 64 Terms Used in Metal Injection Molding
Nickel, and Cobalt Alloys
E407 Practice for Microetching Metals and Alloys
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
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 Dec. 1, 2010. Published January 2011. DOI 10.1520/ Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
F2886–10. 4th Floor, New York, NY 10036, http://www.ansi.org.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from American Society for Quality (ASQ), 600 N. Plankinton Ave.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Milwaukee, WI 53203, http://www.asq.org.
Standards volume information, refer to the standard’s Document Summary page on Available from Metal Powder Industries Federation (MPIF), 105 College Road
the ASTM website. East, Princeton, New Jersey 08540, http://www.mpif.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2886 − 10
3.2 DefinitionsofpowdermetallurgyandMIMtermscanbe 5. Materials and Manufacture
found inTerminology B243 and MPIF Standard 64.Additional
5.1 Components conforming to this specification shall be
descriptive information is available in the Related Material
produced by the metal injection molding process using preal-
Section of Vol. 02.05 of theAnnual Book ofASTM Standards.
loyed metal powders with major elemental composition meet-
3.3 absolute density, n—the value of density used to char-
ing the chemical requirements of Table 1.
acterize a powder material with a particular chemical compo-
5.2 Post-sintering operations may be employed to achieve
sition as if it were a fully dense material, completely free of
the desired density, shape, size, surface finish or other compo-
porosity.
nent properties. The post-sintering operations to be used shall
3.3.1 Discussion—For purposes of this specification, the
be agreed upon between the supplier and purchaser.
skeletal density (also referred to as pycnometer density)
5.3 The condition and finish of the components shall be
measured on the raw material powders using the pycnometry
agreed upon between the supplier and purchaser.
method of Test Method B923 will be used to represent the
absolute density of the particular chemical composition.
6. Chemical Requirements
3.4 debinding, n—a step between molding and sintering
6.1 The components supplied under this specification shall
where the majority of the binder used in molding is extracted
conform to the chemical requirements in Table 1. The supplier
by heat, solvent, a catalyst or other techniques.
shall not ship components with chemistry outside the require-
3.5 feedstock, n—in metal injection molding, a moldable
ments specified in Table 1.
mixture of metal powder and binder.
6.1.1 Chemical analysis of the finished component or rep-
3.6 feedstock batch, n—a specified quantity of feedstock
resentative sample shall be used for reporting all chemical
made up of the same lot of metallic powders and the same lot
requirements. Any representative sample shall be produced
of binder materials mixed under the same conditions at
from the same feedstock batch, debound, sintered, and post
essentially the same time.
processed concurrently with the finished components that it
represents.
3.7 lot, n—a specified quantity of components made up of
6.1.2 Requirements for the major and minor elemental
the same batch of feedstock, debound, sintered and post
constituents are listed in Table 1. Also listed are important
processed under the same conditions at essentially the same
residual elements. The percentage of cobalt is determined by
time.
difference and need not be determined or certified.
3.8 metal injection molded component, n—product fabri-
6.1.3 Analysis for elements not listed in Table 1 is not
cated by a metal injection molding process consisting of
required to verify compliance with this specification.
mixing metal powders with binders to make a feedstock,
6.2 Product Analysis:
introducing this feedstock into a mold by injection or other
6.2.1 Product analysis tolerances do not broaden the speci-
means, debinding to remove the binders, and sintering.
fied heat analysis requirements but cover variations in the
3.9 pre-alloyed powder, n—powder composed of two or
measurement of chemical content between laboratories. The
more elements that are alloyed in the powder manufacturing
product analysis tolerances shall conform to the product
process in which the particles are of the same nominal
tolerances in Table 2.
composition throughout.
6.2.2 The product analysis is either for the purpose of
3.10 relativedensity,n—thedensityratio,oftenexpressedas
verifying the composition of the manufacturing lot or to
apercentage,ofthedensityofaporousmaterialtotheabsolute
density of the same material, completely free of porosity.
TABLE 1 Chemical Requirements
3.11 sintering—the metallurgical bonding of particles in a
Element Chemical Composition Chemical Composition
MIM component resulting from a thermal treatment at a
Alloy 1 Alloy 2
temperature below the melting point of the main constituent.
(Low Carbon) (High Carbon)
(% mass/mass) (% mass/mass)
min max min max
4. Ordering Information
Carbon . 0.14 0.15 0.35
Chromium 27.0 30.0 27.0 30.0
4.1 Include with inquiries and orders for material under this
Molybdenum 5.0 7.0 5.0 7.0
specification the following information:
Nickel . 0.5 . 0.5
4.1.1 Quantity,
Iron . 0.75 . 0.75
Silicon . 1.0 . 1.0
4.1.2 ASTM specification and date of issue,
Manganese . 1.0 . 1.0
4.1.3 Alloy 1 (low carbon) or Alloy 2 (high carbon),
Tungsten . 0.20 . 0.20
4.1.4 Units to be certified—SI or inch-pound, Phosphorus . 0.020 . 0.020
Sulfur . 0.010 . 0.010
4.1.5 Component configuration (engineering drawing
Nitrogen . 0.25 . 0.25
and/or 3D solid model) and dimensional requirements,
Aluminum . 0.10 . 0.10
Titanium . 0.10 . 0.10
4.1.6 Condition (5.3),
Boron . 0.010 . 0.010
4.1.7 Mechanical properties (if applicable),
A
Cobalt . Balance . Balance
4.1.8 Finish (5.3),
A
The percentage of cobalt is determined by difference and need not be deter-
4.1.9 Special Tests (Section 9, Section 10), if any, and
mined or certified.
4.1.10 Other requirements.
F2886 − 10
A,B
TABLE 2 Product Analysis Tolerance
7.2 Representative samples or molded tensile specimens
Element Tolerance Under the Minimum or
shall be produced from the same feedstock batch, debound,
Over the Maximum Limit
sintered and post processed concurrently with the finished
C
Composition (% mass/mass)
components that they represent.
Carbon 0.02
Chromium 0.30
7.2.1 Test specimens machined from components or repre-
Molybdenum 0.15
sentative samples shall be ground, or machined to final
Nickel 0.05
dimensions in accordance Test Methods E8/E8M.
Iron 0.03
Silicon 0.05
7.2.2 Alternate tensile specimen geometries may be agreed
Manganese 0.03
upon by the purchaser and supplier. Some examples of the
Tungsten 0.04
Phosphorus 0.005 configurations for molded tensile specimens are described in
Sulfur 0.003
MPIF Standard 10 and MPIF Standard 50.
D
Nitrogen 0.02
Aluminum 0.02
7.3 Specimens for tensile tests shall be tested in accordance
Titanium 0.02
with Test Methods E8/E8M.
Boron 0.002
A 7.4 Should any test piece not meet the specified
See Test Method E354.
B
See AMS 2269 for chemical check analysis limits except nitrogen.
requirements, test two additional representative test pieces, in
C
Under minimum limit not applicable for elements where only a maximum
the same manner, for each failed test piece. The lot shall be
percentage is indicated.
D
considered in complia
...