ASTM C774-88(2021)

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: C774 − 88 (Reapproved 2021)
Standard Test Method for
Yield Strength of Enameling Steels After Straining and
Firing
This standard is issued under the fixed designation C774; 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.
INTRODUCTION
The strength after strain and fire of a steel is a significant factor in the strength of the final enameled
ware. This test provides a method to quantify the yield strength of enamel steels after straining and
firing by straining duplicate test plates to five different strain levels, exposing to a simulated enamel
fire, and measuring the yield stress with a standardized tensile pull test.
1. Scope 3. Definition
1.1 This test method covers determination of the yield 3.1 quarter lines—imaginary lines parallel to the direction
strength of steel specimens after simulated forming and enamel of rolling, positioned at a distance from the sheet mill edge
firing operations. equal to one quarter of the sheet width.
1.2 The values stated in inch-pound units are to be regarded
4. Summary of Test Method
as the standard. The values given in parentheses are for
information only.
4.1 Representative sheet-steel specimens are selected,
strained in tension to simulate forming, heat treated to simulate
1.3 This standard does not purport to address all of the
enamel firing, and tension tested for determination of yield
safety concerns, if any, associated with its use. It is the
strength.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
5. Significance and Use
mine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accor-
5.1 In the manufacture of porcelain enameled ware, sheet
dance with internationally recognized principles on standard-
steel is subjected to forming operations and subsequently to
ization established in the Decision on Principles for the
firing of the enamel at temperatures, typically, of 1400 to
Development of International Standards, Guides and Recom-
1550 °F (760 to 844 °C). Some steels used for porcelain
mendations issued by the World Trade Organization Technical
enameling are subject to grain growth in critically strained
Barriers to Trade (TBT) Committee.
areas resulting in loss of strength.
5.2 This may lead to easy deformation of the steel and
2. Referenced Documents
damage to the porcelain enamel coating.
2.1 ASTM Standards:
5.3 This test method may be correlated with transit or use
A370 Test Methods and Definitions for Mechanical Testing
tests to evaluate the suitability of steel for porcelain enameled
of Steel Products
ware.
E8 Test Methods for Tension Testing of Metallic Materials
[Metric] E0008_E0008M
6. Apparatus
6.1 Shear for cutting blanks.
This test method is under the jurisdiction ofASTM Committee B08 on Metallic
and Inorganic Coatings and is the direct responsibility of Subcommittee B08.12 on
6.2 Equipment for cutting or machining tension specimens.
Materials for Porcelain Enamel and Ceramic-Metal Systems.
6.3 Gage, 2-in. (50.8-mm), for marking tension specimens.
Current edition approved April 1, 2021. Published May 2021. Originally
approvedin1974.Lastpreviouseditionapprovedin2016asC774 – 88(2016).DOI:
6.4 Tension-Testing Equipment, as described in Test Meth-
10.1520/C0774-88R21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or ods and Definitions A370.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
6.5 Specimen-Supporting Rack, slotted to support speci-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. mens on edge spaced 1 in. (25.4 mm) apart.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Co
...