Реферат This specification covers laser-fused stainless steel bars, plates, and shapes of structural quality for use in bolted or welded structural applications. The butt-welded test pieces are welded using laser fusion and then machined into tensile test bars and root-bend test specimens. The term laser fusion is used in this specification to refer to a joining process that is able to produce a coalescence of material using the heat obtained from the application of a concentrated coherent light beam impinging on the surface of a weld joint. Область применения

1.1 This specification covers laser and laser hybrid welded stainless steel bars, plates, sharp-cornered profile (SCP), and built-up shapes of structural quality for use in bolted or welded structural applications. SCP and built-up shapes are used in, but not limited to, the following applications: industrial and general structural applications like buildings, including architecturally exposed steel structures (AESS); architectural steel profiles, such as curtain wall and staircases.

Note 1: The term laser fusion is also used to describe laser welding.

1.1.1 Supplementary requirements of an optional nature are provided. They shall apply only when specified by the purchaser.

Note 2: Since the product covered by this specification is manufactured in small lots on dedicated production lines, minimum product quality requirements are ensured by requiring welding process specification and operator qualification at each manufacturing facility in accordance with AWS, ASME, or ISO requirements. If required, the purchaser can specify higher levels of weld inspection; supplementary requirements for mechanical and corrosion testing; and other requirements.

Note 3: Because of the varying requirements of the end-use applications, different length tolerance and weld inspection levels may be specified.

1.2 Shapes covered in this specification include those defined in Article 3.1.2 of Specification A6/A6M, square and rectangular hollow sections, and additional shapes, including customized, that are made from two or more shapes, plates, bar, sheet, or strip.

1.3 This specification establishes the minimum requirements for manufacturing of laser and laser hybrid welded stainless steel shapes and requires the welds to, at a minimum, match the tensile and yield strength of the base metal. If base metals of different strengths are used, the lower strength base metal shall be matched.

1.4 This specification refers to Specifications A240/A240M, A276/A276M, or A479/A479M for chemical requirements, but the mechanical test requirements are determined by the mechanical properties section of this standard. This standard includes four strength grades. The default strength grade 1 is determined by the base metal standard. Grades 2 through 4 are for specification of higher strength levels.

1.5 The text of this specification contains notes and footnotes that provide explanatory material. Such notes and footnotes, excluding those in tables and figures, do not contain any mandatory requirements.

1.6 Units—This specification is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable M specification designation (SI units), the inch-pound units shall apply. The values stated in either 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 may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.

1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.8 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.