ASTM F879

This specification covers the chemical and mechanical requirements for stainless steel hexagon socket button and flat countersunk head cap screws intended for use in applications requiring general corrosion resistance. The following three conditions are covered: austenitic alloy group 1 AF in an annealed condition, austenitic alloy group 1 CW in a cold-worked condition, and austenitic alloy group 1 CW1 in a cold worked condition. Screws shall be formed by upsetting or extruding, or both and shall be roll threaded and annealed to obtain maximum corrosion resistance and minimum permeability. The chemical composition, which shall be determined by chemical analysis, shall conform to the requirements for carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, copper, and molybdenum. The screws shall be subjected to tension tests and shall conform to the breaking strength, tensile strength, extension, yield strength, elongation, and Vickers and Rockwell hardness requirements. Corrosion test shall also be conducted to determine the susceptibility of the specimens to intergranular corrosion.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

1.1 This specification covers the chemical and mechanical requirements for stainless steel inch hexagon socket button (SBHCS) and flat countersunk (SFHCS) head cap screws with nominal thread 0.060 through 0.625 in. intended for use in applications requiring general corrosion resistance.

1.2 The following three conditions are covered:

1.2.1 Austenitic alloy group 1 AF in an annealed condition at 85 ksi maximum,

1.2.2 Austenitic alloy group 1 CW in a cold-worked condition at 80 ksi minimum, and

1.2.3 Austenitic alloy group 1 condition CW1 in a cold worked condition at 102 ksi minimum.

1.3 Units—The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 The following precautionary caveat pertains only to the test method portion, Section 12, of this specification: 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.

2. Referenced Documents

ASTM Standards
A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
A342/A342M Test Methods for Permeability of Feebly Magnetic Materials
A380 Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems
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
A967 Specification for Chemical Passivation Treatments for Stainless Steel Parts
D3951 Practice for Commercial Packaging
E18 Test Methods for Rockwell Hardness of Metallic Materials
E384 Test Method for Microindentation Hardness of Materials
E92 Test Method for Vickers Hardness of Metallic Materials
F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection
F593 Specification for Stainless Steel Bolts, Hex Cap Screws, and Studs
F606 Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets
F788/F788M Specification for Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series
ASME Standard
B18.3 Socket Cap, Shoulder and Set Screws (Inch Series)

Index Terms

corrosion resistant; stainless steel; socket button head cap screws; socket flat countersunk head cap screws; Countersunk head cap screws--specifications; Head cap screws; Screws--specifications; Stainless steel screws--specifications; Steel screws--specifications; ICS Number Code 21.060.10 (Bolts, screws, studs)

Citing ASTM Standards

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