ASTM A924/A924M-99

1.1 This specification covers the general requirements that, unless otherwise specified in the product specification, apply to steel sheet in coils and cut lengths, metallic-coated on continuous lines by the hot-dip process. The product is intended for applications requiring corrosion resistance and may require specific strength levels, heat resistance, paintability, or formability, or a combination thereof.

1.2 Subject to individual product specification provisions, steel sheet may be available in commercial quality (CQ), lock-forming quality (LFQ), drawing quality (DQ), drawing quality special killed (DQSK), structural quality (SQ), and high-strength, low-alloy (HSLA). Steel sheet can be produced with the following metallic coatings. Specific information on each of the following is contained in the individual product specification:

1.2.1 Zinc or zinc-iron alloy coated,

1.2.2 Zinc-5% aluminum alloy coated,

1.2.3 55% aluminum-zinc alloy coated,

1.2.4 Aluminum-coated, and

1.2.5 Terne (lead-tin alloy) coated.

1.3 Products covered by this general requirements specification are described in the following product standards: Specifications A308; A463/A463M; A653/A 653M; A755/A755M; A792/A792M; A819; A875/A875M; and A929/A929M.

1.4 Metallic-coated steel sheet is produced to various coating designations, as shown in the individual product specifications. Except for differentially coated sheet, the coating is always expressed as the total coating of both surfaces.

1.5 In case of any conflict in requirements, the requirements of the individual product specifications shall prevail over those of this general specification.

1.6 The purchaser may specify additional requirements that do not negate any of the provisions of this general specification or of the individual product specifications. Such additional requirements, the acceptance of which are subject to negotiation with the supplier, should be included in the order information.

1.7 For purposes of determining conformance with this specification and the various product specifications referenced in 1.3, values shall be rounded to the nearest unit in the right-hand place of figures used in expressing the limiting values (except to the nearest 5 MPa for SI strength values) in accordance with the rounding method of Practice E29.

1.8 Metallic-coated steel sheet covered by this specification is produced to thickness requirements expressed to 0.001 in. [0.01 mm] for both coils and cut lengths. The thickness is the total of the base steel and the coating.

1.9 The values stated in inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with this specification.

1.10 This specification and some of the applicable product specifications are expressed in both inch-pound and SI units. However, unless the order specifies the applicable "M" specification designation (SI units), the product shall be furnished to inch-pound units.