Full Description

This standard covers the requirements for hot dip coatings, bothgalvanized and galvannealed,applied to a sheet steel substrate utilizing a continuous hot dipprocess. The substrate may becold or hot rolled sheet steel. Additional requirements or agreementsshall be specified by thelocal business units (e.g., NAO, Opel ITDC, GM do Brasil, Holden Ltd.,etc.).

Material Description. The type of coating and its mass and finish arespecified by suffixes addedto the basic specification number. The first two letters HD willdesignate a continuous hot dipcoating. The coating mass for each side is designated by a minimumvalue in g/m². Onlycoating masses of 45 g/m² , 52 g/m² , 60 g/m², 70g/m² or 90 g/m² shall beused unless Materials Engineering is consulted. Differentially coatedproducts may be specified.Other coating masses shall follow the same designation method. Theletter G designates a pure zinccoating (galvanized) and the letter A designates a zinc-iron alloy(galvannealed) coating. Thefirst set of digits along with the letter designation specifies thecoating parameters of theunexposed side. The remaining designation specifies E (exposed), Z(semi-exposed) or U (unexposed).