Effect of Galvanizing Conditions on the Tensile Properties of High Strength Steel

Specimen of Circular Cross Section Coated on the All Surface

Abstract

Experiments were carried out in accordance with a design of experiment and the following results were obtained.
(1) For high strength low alloy structural steel with a grade of 80kgf/mm², difference in galvanizing conditions had no effect on elongation or reduction of area.
The cooling method affected yield point, and the yield point of specimens that were air-cooled after galvanizing was lower than that of water-cooled specimens.
Dipping times affected tensile strength, and the value decreased with an increase in dipping time.
The effect on HT 80 B-steel was minor for all properties investigated, but an effect was on HT 80 A-steel with a thin galvanized layer.
(2) For high strength bolt steel with a grade between 80 and 120kgf/mm², the hardness of the LCB-steel was reduced by dipping at a bath temperature higher than the tempering temperature. All tensile properties were decreased by galvanizing.
Yield point and tensile strength of the SNCM-steel were not affected by galvanizing. Elongation and reduction of area of steel galvanized after blasting were decreased by the high-notch sensitivity of the steel.