【国外标准】 Standard Specification for Steel Bars, Carbon, Merchant Quality, Mechanical Properties

This specification covers hot-wrought merchant quality carbon steel bars and bar size shapes produced to mechanical property requirements and intended for noncritical constructional applications. The bars shall be available in round, square and hexagonal shapes. The steel shall be made by the open-hearth, basic-oxygen, or electric-furnace process. The specimens shall undergo a tension test to determine tensile strength, yield point and elongation. The merchant quality bars shall be from visible pipe; however, they may contain pronounced chemical segregation. Internal porosity, surface seams, and other surface irregularities may be present in this quality. The bars shall also be furnished as rolled and not pickled, blast cleaned, or oiled.1.1 This specification covers hot-wrought merchant quality carbon steel bars and bar size shapes produced to mechanical property requirements and intended for noncritical constructional applications (see 8.2).1.2 Merchant quality hot-wrought steel bar is available in the following ranges of size and section:1.2.1 Rounds, squares, and hexagons with diameters or distance across flats under 3 in. [75 mm].1.2.2 Bar size shapes with maximum dimensions under 3 in. [75 mm].1.2.3 Other bar sections with weight per foot under 40.84 lb/ft [60.78 kg/m].1.2.4 Flats 6 in. [152 mm] or under in width, over 0.203 in. [over 5 mm in thickness up to 150 mm in width] in thickness, and under 40.84 lb/ft or 12 in.2 [77.4 cm2] in cross-sectional area.1.2.5 Flats over 6 in. to 8 in., inclusive in width, 0.230 in. and over [over 6 mm in thickness and over 50 mm through 200 mm in width] in thickness and under 40.84 lb/ft [60.78 kg/m] or 12 in.2 [77.4 cm2] in cross-sectional area.1.2.6 Hot-wrought merchant quality carbon steel bars subject to mechanical property requirements are hot wrought in straight lengths only.1.3 Some applications may require one or more of the available designations shown under supplementary requirements.NOTE 1: Special quality hot-wrought carbon steel bars subject to mechanical property requirements are covered in Specification A675/A675M.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.