ASTM F1137/F1137M-19
(Specification)Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners
Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners
ABSTRACT
This specification covers the basic physical requirements and test methods for phosphate/oil and phosphate/organic corrosion protective coatings for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection. The zinc phosphate treatment and subsequent protective coatings are classified into seven grades according to the following requirements: Grade 0A consists of a zinc phosphate coating with no additional sealer (dry); Grade 0B consists of a zinc phosphate coating with a dry organic sealer; Grades 0C, 0D, and I consist of a zinc phosphate coating with supplemental protective oil type compound; and Grades II and III consist of a zinc phosphate with a supplemental zinc-rich epoxy resin coating (with the addition of a clear organic topcoat for Grade II). These coatings may or may not have a decorative finish. The coatings shall meet the requirements specified for appearance, adhesion, corrosion resistance, coating flexibility, thread fit, and dry-to-touch characteristics. In addition, they shall also undergo humidity and coating thickness tests.
SCOPE
1.1 This specification covers the basic requirements for six grades of corrosion protection for fasteners. Grade A consists of a heavy zinc phosphate coating with no additional sealer (dry), Grade B consists of a heavy zinc phosphate coating with a dry organic sealer, Grade C consists of a heavy zinc phosphate coating with supplemental dry-to-touch oil type compound, Grade D consists of a heavy zinc phosphate coating with supplemental protective oil type compound, Grade E consists of a grain-refined microcrystalline zinc phosphate with supplemental oil type compound, and Grade F consists of a manganese phosphate coating with supplemental oil type compound.
1.2 This specification is intended primarily for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection and lubrication.
1.3 These coatings may or may not have a decorative finish.
1.4 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.
1.5 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
- 14-Jun-2019
- Technical Committee
- F16 - Fasteners
- Drafting Committee
- F16.03 - Coatings on Fasteners
Relations
- Effective Date
- 15-Jun-2019
- Effective Date
- 01-Jan-2024
- Effective Date
- 01-Feb-2018
- Effective Date
- 15-Nov-2012
- Effective Date
- 01-Oct-2011
- Effective Date
- 01-Jul-2009
- Effective Date
- 01-Jan-2009
- Effective Date
- 15-Dec-2007
- Effective Date
- 01-Mar-2007
- Effective Date
- 01-Oct-2003
- Effective Date
- 10-Oct-2002
- Effective Date
- 10-Apr-2002
- Effective Date
- 10-Apr-2002
- Effective Date
- 10-Apr-1997
Overview
ASTM F1137/F1137M-19: Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners establishes requirements for corrosion-resistant coatings applied to ferrous fasteners, such as nuts, clips, washers, and threaded or non-threaded hardware. This standard details the classification, physical requirements, and test methods for phosphate/oil and phosphate/organic coatings, which provide critical protection against rust and enhance the service life of fasteners used across multiple industries.
The specification covers six grades of coatings, utilizing heavy zinc phosphate, microcrystalline zinc phosphate, and manganese phosphate, sometimes supplemented by oil or organic compounds to ensure optimal corrosion resistance. Coating grades are differentiated by their composition and intended protective performance to suit a variety of operational environments.
Key Topics
- Phosphate Coating Types: Covers heavy zinc, microcrystalline zinc, and manganese phosphate coatings.
- Supplemental Coatings: Oil-type compounds and organic sealers to improve corrosion protection and lubrication.
- Coating Grades:
- Grade A: Heavy zinc phosphate, no sealer (dry)
- Grade B: Heavy zinc phosphate, dry organic sealer
- Grade C: Heavy zinc phosphate, dry-to-touch oil compound
- Grade D: Heavy zinc phosphate, protective oil-type compound
- Grade E: Microcrystalline zinc phosphate with oil compound
- Grade F: Manganese phosphate with oil compound
- Performance Criteria: Requirements for appearance, adhesion, corrosion resistance, coating thickness, flexibility, thread fit, and dry-to-touch properties.
- Test Methods: Salt spray testing (ASTM B117) for corrosion resistance, weigh-strip-weigh for coating weight measurement, and evaluation of coating thickness and thread fit.
- Metric and Imperial Units: Specifies use of either SI units or inch-pound units independently for compliance.
Applications
The requirements in ASTM F1137/F1137M-19 are essential for industries where fastener durability and corrosion resistance are critical, including:
- Automotive Manufacturing: Fastener coatings protect against exposure to moisture, salt, and other corrosive agents found in transportation environments.
- Construction: Structural fasteners in buildings and infrastructure benefit from increased resistance to atmospheric and environmental corrosion.
- Industrial Machinery: Properly coated hardware extends equipment life and reduces maintenance costs by preventing rust and seizing.
- Utilities and Energy: Fasteners in electrical, water, and gas infrastructure must maintain integrity over long service intervals.
- OEM and MRO Supply Chains: Ensures that replacement and original equipment fasteners meet stringent quality and performance benchmarks for corrosion protection and thread fit.
By specifying the grade and type of coating, users can tailor fastener performance to the specific demands of their application environment, optimizing both longevity and reliability.
Related Standards
For quality assurance and comprehensive corrosion protection strategies, ASTM F1137/F1137M-19 is commonly referenced alongside:
- ASTM B117 – Standard Practice for Operating Salt Spray (Fog) Apparatus: Used for evaluating corrosion resistance of coated fasteners.
- ASTM F1470 – Standard Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection.
- ISO 9227 – Corrosion tests in artificial atmospheres (salt spray tests).
- ASTM F1941/F1941M – Electroplated coatings for fasteners.
- ASTM A153/A153M – Zinc coating (hot-dip galvanizing) on iron and steel hardware.
These related guidelines together ensure that fastener coatings deliver the intended protective performance, supporting compliance in regulated industries, and meeting international procurement and quality management requirements.
Keywords: phosphate coatings, oil coatings, corrosion resistance, protective coatings for fasteners, zinc phosphate, manganese phosphate, ASTM F1137, salt spray test, fastener durability, industrial coatings, thread fit compliance.
Buy Documents
ASTM F1137/F1137M-19 - Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners
REDLINE ASTM F1137/F1137M-19 - Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners
Get Certified
Connect with accredited certification bodies for this standard
National Aerospace and Defense Contractors Accreditation Program (NADCAP)
Global cooperative program for special process quality in aerospace.
CARES (UK Certification Authority for Reinforcing Steels)
UK certification for reinforcing steels and construction.
DVS-ZERT GmbH
German welding certification society.
Sponsored listings
Frequently Asked Questions
ASTM F1137/F1137M-19 is a technical specification published by ASTM International. Its full title is "Standard Specification for Phosphate/Oil Corrosion Protective Coatings for Fasteners". This standard covers: ABSTRACT This specification covers the basic physical requirements and test methods for phosphate/oil and phosphate/organic corrosion protective coatings for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection. The zinc phosphate treatment and subsequent protective coatings are classified into seven grades according to the following requirements: Grade 0A consists of a zinc phosphate coating with no additional sealer (dry); Grade 0B consists of a zinc phosphate coating with a dry organic sealer; Grades 0C, 0D, and I consist of a zinc phosphate coating with supplemental protective oil type compound; and Grades II and III consist of a zinc phosphate with a supplemental zinc-rich epoxy resin coating (with the addition of a clear organic topcoat for Grade II). These coatings may or may not have a decorative finish. The coatings shall meet the requirements specified for appearance, adhesion, corrosion resistance, coating flexibility, thread fit, and dry-to-touch characteristics. In addition, they shall also undergo humidity and coating thickness tests. SCOPE 1.1 This specification covers the basic requirements for six grades of corrosion protection for fasteners. Grade A consists of a heavy zinc phosphate coating with no additional sealer (dry), Grade B consists of a heavy zinc phosphate coating with a dry organic sealer, Grade C consists of a heavy zinc phosphate coating with supplemental dry-to-touch oil type compound, Grade D consists of a heavy zinc phosphate coating with supplemental protective oil type compound, Grade E consists of a grain-refined microcrystalline zinc phosphate with supplemental oil type compound, and Grade F consists of a manganese phosphate coating with supplemental oil type compound. 1.2 This specification is intended primarily for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection and lubrication. 1.3 These coatings may or may not have a decorative finish. 1.4 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. 1.5 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.
ABSTRACT This specification covers the basic physical requirements and test methods for phosphate/oil and phosphate/organic corrosion protective coatings for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection. The zinc phosphate treatment and subsequent protective coatings are classified into seven grades according to the following requirements: Grade 0A consists of a zinc phosphate coating with no additional sealer (dry); Grade 0B consists of a zinc phosphate coating with a dry organic sealer; Grades 0C, 0D, and I consist of a zinc phosphate coating with supplemental protective oil type compound; and Grades II and III consist of a zinc phosphate with a supplemental zinc-rich epoxy resin coating (with the addition of a clear organic topcoat for Grade II). These coatings may or may not have a decorative finish. The coatings shall meet the requirements specified for appearance, adhesion, corrosion resistance, coating flexibility, thread fit, and dry-to-touch characteristics. In addition, they shall also undergo humidity and coating thickness tests. SCOPE 1.1 This specification covers the basic requirements for six grades of corrosion protection for fasteners. Grade A consists of a heavy zinc phosphate coating with no additional sealer (dry), Grade B consists of a heavy zinc phosphate coating with a dry organic sealer, Grade C consists of a heavy zinc phosphate coating with supplemental dry-to-touch oil type compound, Grade D consists of a heavy zinc phosphate coating with supplemental protective oil type compound, Grade E consists of a grain-refined microcrystalline zinc phosphate with supplemental oil type compound, and Grade F consists of a manganese phosphate coating with supplemental oil type compound. 1.2 This specification is intended primarily for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection and lubrication. 1.3 These coatings may or may not have a decorative finish. 1.4 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. 1.5 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.
ASTM F1137/F1137M-19 is classified under the following ICS (International Classification for Standards) categories: 21.060.01 - Fasteners in general; 25.220.60 - Organic coatings. The ICS classification helps identify the subject area and facilitates finding related standards.
ASTM F1137/F1137M-19 has the following relationships with other standards: It is inter standard links to ASTM F1137/F1137M-18, ASTM F1470-24, ASTM F1470-18, ASTM F1470-12, ASTM B117-11, ASTM B117-09, ASTM F1470-09, ASTM B117-07a, ASTM B117-07, ASTM B117-03, ASTM B117-02, ASTM F1470-01, ASTM F1470-02, ASTM B117-97. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
ASTM F1137/F1137M-19 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
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:F1137/F1137M −19
Standard Specification for
Phosphate/Oil Corrosion Protective Coatings for Fasteners
This standard is issued under the fixed designation F1137/F1137M; 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* F1470 Practice for Fastener Sampling for Specified Me-
chanical Properties and Performance Inspection
1.1 This specification covers the basic requirements for six
grades of corrosion protection for fasteners. Grade A consists
3. Classification
of a heavy zinc phosphate coating with no additional sealer
(dry), Grade B consists of a heavy zinc phosphate coating with
3.1 The phosphate treatments and subsequent protective
a dry organic sealer, Grade C consists of a heavy zinc
coatings are classified into six grades according to the require-
phosphate coating with supplemental dry-to-touch oil type
ments shown in Table 1.
compound,GradeDconsistsofaheavyzincphosphatecoating
with supplemental protective oil type compound, Grade E
4. Ordering Information
consistsofagrain-refinedmicrocrystallinezincphosphatewith
4.1 Orders for material under this specification shall include
supplemental oil type compound, and Grade F consists of a
the following information:
manganese phosphate coating with supplemental oil type
4.1.1 Quantity of parts,
compound.
4.1.2 Grade required (see Table 1), and
1.2 This specification is intended primarily for fasteners
4.1.3 Any additions agreed upon between the purchaser and
such as nuts, clips, washers, and other ferrous threaded and
the supplier.
non-threaded fasteners that require corrosion protection and
lubrication.
5. Requirements
1.3 These coatings may or may not have a decorative finish.
5.1 Appearance—Unless otherwise agreed upon between
1.4 The values stated in either SI units or inch-pound units the purchaser and the producer, the color of the protective
are to be regarded separately as standard. The values stated in coating shall be as-coated gray for all grades.
each system may not be exact equivalents; therefore, each
5.2 Corrosion Resistance—These coatings shall be capable
system shall be used independently of the other. Combining
of withstanding neutral salt spray for the minimum h specified
values from the two systems may result in non-conformance
in Table 1 with no base metal corrosion on significant surfaces.
with the standard.
Significant surfaces on threaded fasteners are defined as the
1.5 This international standard was developed in accor-
exposed surfaces when the fasteners are installed in a normal
dance with internationally recognized principles on standard-
manner (bolt head, nut head, face, etc.). On other surfaces
ization established in the Decision on Principles for the
where control of the coating cannot be obtained under normal
Development of International Standards, Guides and Recom-
processing such as holes, recesses, threads, etc., the above
mendations issued by the World Trade Organization Technical
requirements do not apply.
Barriers to Trade (TBT) Committee.
5.3 Thread Fit—The maximum thickness of coating which
2. Referenced Documents may be applied to threads on threaded products is limited by
2 the basic thread size (see 8.2). Threads may be produced
2.1 ASTM Standards:
undersize/oversize (before coating) to accommodate the coat-
B117 Practice for Operating Salt Spray (Fog) Apparatus
ing thickness, providing the finished product (after coating)
meets all specified mechanical properties. All undersize/
This specification is under the jurisdiction of ASTM Committee F16 on
oversize must be within permissible limits as agreed upon
Fasteners and is the direct responsibility of Subcommittee F16.03 on Coatings on
Fasteners.
between the supplier and the purchaser.
Current edition approved June 15, 2019. Published June 2019. Originally
5.4 Dry-to-Touch—Grades B and C shall be evenly coated
approved in 1988. Last previous edition approved in 2018 as F1137/F1137M – 18.
DOI: 10.1520/F1137_F1137M–19.
and dry-to-touch such that when held with filter paper or
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
equivalent and applying hand pressure for 5 to 10 s, there shall
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
be no visible staining of the filter paper when viewed without
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. use of supplementary magnification. For referee purposes, this
*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
F1137/F1137M−19
TABLE 1 Clas
...
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: F1137/F1137M − 18 F1137/F1137M − 19
Standard Specification for
Phosphate/Oil Corrosion Protective Coatings for Fasteners
This standard is issued under the fixed designation F1137/F1137M; 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*
1.1 This specification covers the basic requirements for six grades of corrosion protection for fasteners. Grade A consists of a
heavy zinc phosphate coating with no additional sealer (dry), Grade B consists of a heavy zinc phosphate coating with a dry organic
sealer, Grade C consists of a heavy zinc phosphate coating with supplemental dry-to-touch oil type compound, Grade D consists
of a heavy zinc phosphate coating with supplemental protective oil type compound, Grade E consists of a grain-refined
microcrystalline zinc phosphate with supplemental oil type compound, and Grade F consists of a manganese phosphate coating
with supplemental oil type compound.
1.2 This specification is intended primarily for fasteners such as nuts, clips, washers, and other ferrous threaded and
non-threaded fasteners that require corrosion protection and lubrication.
1.3 These coatings may or may not have a decorative finish.
1.4 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.
1.5 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:
B117 Practice for Operating Salt Spray (Fog) Apparatus
F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection
3. Classification
3.1 The phosphate treatments and subsequent protective coatings are classified into six grades according to the requirements
shown in Table 1.
4. Ordering Information
4.1 Orders for material under this specification shall include the following information:
4.1.1 Quantity of parts,
4.1.2 Grade required (see Table 1), and
4.1.3 Any additions agreed upon between the purchaser and the supplier.
5. Requirements
5.1 Appearance—Unless otherwise agreed upon between the purchaser and the producer, the color of the protective coating
shall be as-coated gray for all grades.
5.2 Corrosion Resistance—These coatings shall be capable of withstanding neutral salt spray for the minimum h specified in
Table 1 with no base metal corrosion on significant surfaces. Significant surfaces on threaded fasteners are defined as the exposed
This specification is under the jurisdiction of ASTM Committee F16 on Fasteners and is the direct responsibility of Subcommittee F16.03 on Coatings on Fasteners.
Current edition approved June 1, 2018June 15, 2019. Published August 2018June 2019. Originally approved in 1988. Last previous edition approved in 20112018 as
ɛ1
F1137 – 11F1137/F1137M – 18. . DOI: 10.1520/F1137-18.10.1520/F1137_F1137M–19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. 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
F1137/F1137M − 19
TABLE 1 Classification and Performance Requirements of Protective Coatings
Grade Phosphate Coating Weight Supplemental Coating Thickness, Salt Spray,
Treatment Coating μm h
2 2
mg/ft g/m[g/m ]
A
Grade A Heavy Zinc Phosphate 1000, min 11, min none see 5.3 72
A
Grade A Heavy Zinc Phosphate 1000, min [11, min] none see 5.3 72
Grade B Heavy Zinc Phosphate 1000, min 11, min sealer see 5.3 72
Grade B Heavy Zinc Phosphate 1000, min [11, min] sealer see 5.3 72
Grade C Heavy Zinc Phosphate 1000, min 11, min protective oil-type see 5.3 24
compound
(dry-to-touch)
Grade C Heavy Zinc Phosphate 1000, min [11, min] protective oil-type see 5.3 24
compound
(dry-to-touch)
Grade D Heavy Zinc Phosphate 1000, min 11, min protective oil-type see 5.3 72
compound
Grade D Heavy Zinc Phosphate 1000, min [11, min] protective oil-type see 5.3 72
compound
Grade E Microcrystalline 185 min– 2 min –7 protective oil-type see 5.3 8
B
Zinc Phosphate 650 max max compound
Grade E Microcrystalline 185 min– [2 min –7 protective oil-type see 5.3 8
B
Zinc Phosphate 650 max max] compound
Grade F Manganese Phosphate 370 min 4 min– 19 protective oil-type see 5.3 24
–1765 max max compound
Grade F Manganese Phosphate 370 min [4 min– 19 protective oil-type see 5.3 24
–1765 max max] compound
A
When testing Grade A finished pa
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...