1 This International Standard specifies the minimum requirements for steel sheet, in coils and cut lengths, metallic-coated by the continuous hot-dip process, with zinc-5 % aluminium alloy coating.
2 The product is intended for applications requiring corrosion resistance, formability and paintability.
3 The steel sheet is produced in a number of qualities and grades, coating mass, surface treatments and coating conditions designed to be compatible with differing application requirements.
4 The product is produced in two types:
— T1: zinc-5 % aluminium-mischmetal alloy coating,
— T2: zinc-5 % aluminium-0,1 % magnesium alloy coating.
NOTE There may be differences in product characteristics between Type 1 and Type 2 coated steel sheet, depending on the intended application.
5 Zinc-5 % aluminium alloy coated steel sheet is produced in thicknesses up to 5 mm after coating, and in widths of 600 mm and over in coils and cut lengths. Zinc-5 % aluminium alloy coated steel sheet less than 600 mm wide may be slit from wide sheet and will be considered as sheet.
6 The thickness of zinc-5 % aluminium alloy coated sheet steel may be specified as a combination of the base metal and metallic coating, or as the base metal alone. The purchaser shall indicate on the order which method of specifying thickness is required. In the event that the purchaser does not indicate any preference, the thickness as a combination of the base metal and coating will be provided. Annex A describes the requirements for specifying the thickness of the base metal alone.
7 Zinc-5 % aluminium alloy coated steel sheet may be ordered in one of two conditions as described in 4.2.1:
a) Condition A) Steel ordered to satisfy mechanical property requirements,
b) Condition B) Steel when ordered to make an identified part.
8 Zinc-5 % aluminium alloy coated steel sheet is available in several fabrication qualities.
— Commercial: intended for general fabrication purposes, where sheet is used in the flat or for bending or moderate forming.
— Drawing: intended for fabricating parts where drawing or severe forming may be involved.
— Deep drawing-aluminium killed (non-aging): intended for fabricating parts where particularly severe drawing or forming may be involved or essential freedom from aging is required.
— Extra deep drawing (stabilized interstitial free): intended for applications requiring interstitial-free steel (IF) which is non-aging and has maximum formability.
— Structural: zinc-5 % aluminium alloy coated steel sheet is produced in six grades as defined by a minimum yield stress.
ISO 14788:2005 history
2017ISO 14788:2017 Steel sheet, zinc-5 % aluminium alloy-coated by the continuous hot-dip process, of commercial, drawing and structural qualities