Tài liệu tham khảo giáo trình nhôm trong thiết kế xây dựng - Chương 4 Aluminium alloys and their properties NUMBERING SYSTEM FOR WROUGHT ALLOYS Basic system The American system for designating wrought aluminium materials, administered by the Aluminum Association (AA) in Washington, is by now virtually standard worldwide [12]. For any given material, it employs a two-part reference number, . 3103–H14, 6082–T6 or 5083–0. | CHAPTER 4 Aluminium alloys and their properties NUMBERING SYSTEM FOR WROUGHT ALLOYS Basic system The American system for designating wrought aluminium materials administered by the Aluminum Association AA in Washington is by now virtually standard worldwide 12 . For any given material it employs a two-part reference number . 3103-H14 6082-T6 or 5083-0. The four-figure number before the hyphen defines the alloy and the symbols after it the condition or temper in which that alloy is supplied. Aluminium alloys can be either non-heat-treatable or heat-treatable. The former are available in a range of work-hardened conditions defined by an H-number as in the first example above while the latter are supplied in various conditions of heat treatment specified in terms of a T-number second example . Standardization of alloys The four-figure number before the hyphen relates to a chemical composition . an alloy. The AA supply a document Registration Record of International Alloy Designations which lists the reference numbers of all the alloys registered with them together with their compositions. The list runs to several hundred and is regularly updated. The new European EN standards have adopted the same alloy numbers but prefixed by the letters AW Aluminium Wrought . Thus in the European system 6082 alloy is officially referred to as AW-6082 although in common speech it is normal to omit the AW. The following illustrates the way in which a composition is specified using the alloy 6082 as an example Si Mn Mg Fe Cu Cr Zn Copyright 1999 by Taylor Francis Group. All Rights Reserved. Where a range is given as for the first three elements this denotes the minimum and maximum permitted content of an intended ingredient. Where a single figure is given as for the last four this refers to an impurity which must not exceed the value quoted. This is the official way of specifying such an alloy. In everyday parlance it is .