ASTM C774:88(R2021) pdf free download – Standard Test Method for Yield Strength of Enameling Steels After Straining and Firing.
3.1 quarter line.s—iinagtnary lines parallel to the direction of wiling. posittoird at a distance from the sheet mill edge equal to one quarter of the sheet widih,
4. Sunsinan at ‘frid Method
4.1 Representative sheet-steel specimens are ,eiected. strained in tension to simuljai. voting, heat treated to simulate enamel firing, and tension tested trw determination of yield strength,
S. Signilkance
5.1 In the manufacture of porcelain enameled ware, sheet steel is subjected to forming operations and sahsequently to hAng of the enamel at temperatures. typically. of 144W) to l55OF 1761) to 1144°C). Some sleek used ror porcelain enameling are subject to grain growth in critically strained areas mulLing in loss of strength.
5.2 This may lead to eaay deformation of the steel and damage to the porcelain enamel coating.
5.3 This test method may he correlated with transit or use tests to evaluate the suitability of steel for porcelain enameled watt.
6. Apparatus
6.1 .Sheur for catting blanks.
6.2 E.qu4mrneni for cutting a machining tension specimen.s.
6.3 Gage, 2-in. t50.X.mm), for marking tension specimens.
6.4 Tension-Testing tqtdpnent. as described in lest Methrids and flelinitions A37ti.
6.5 .Sperunen-Stqiporring Rock.. slotted to support spedinens cia edge spaced I in. 125.4 mmt apart.
Ms Fanaart capable of heating the test specimena and their sulipotling rack to the tiring temperature in 2 mm.
7. Reagents and Materials
7.1 Sheet Steel, sulbcpent in sire to provide the test specimen. deteribed in Section 8.
72 Soln,L such as acetone or isopropyl alcohol.
9.1 Remove burrs 1mm the cut edges of the test samples.
9.2 Mat 2-in. (50.K-tnm gage lengths in the middle of the test samples and strain tn tension. Maintain a nunitnum of I in. (25.4 mm) of length between the grips of the tensmon.testing machine and the gage marks.
9.3 Elongate duplicate test samples to nominal strain levels of 0. 8. 12. Itt. and 20%. Measure the elongation with estcnsonrten, dividers, or other ,nean,s.
9.4 kemose the test samples (nan the tension machine and measure actual strain to the nearest 001 in. (0.25 mm).