A hot-dip galvanized steel sheet with excellent weldability and corrosion resistance and preparation method thereof

Abstract

The invention discloses a hot-dip galvanized steel sheet with excellent welding performance and corrosion resistance and a preparation method thereof. The preparation method comprises the following steps: degreasing and cleaning the steel strip after uncoiling and welding, scrubbing with hot water, squeezing with a drying roller and blowing with hot air to obtain a clean steel strip; the clean steel strip is placed in an annealing furnace filled with a reducing atmosphere Carry out annealing; hot-dip galvanize the annealed steel strip, keep the angle of the upper and lower air knives consistent in the hot-dip galvanization, and both are negative angles; after the galvanized steel strip is air-cooled, water-cooled and squeezed dry, it is skin-passed Surface quenching and tempering treatment; passivation treatment on the hot-dip galvanized steel sheet after smoothing and straightening; oiling or non-oiling anti-corrosion protection treatment on the hot-dip galvanized steel sheet after passivation treatment. By controlling air knife parameters, skin pass parameters, passivation process, etc., a high-corrosion-resistant hot-dip galvanized steel sheet with excellent welding performance and corrosion resistance is produced, and the welding window of the produced differential-thickness coating product is wide. , excellent welding performance.

Description

technical field [0001] The invention belongs to the technical field of production and processing of hot-dip galvanized steel sheets, and in particular relates to a hot-dip galvanized steel sheet with excellent welding performance and corrosion resistance and a preparation method thereof. Background technique [0002] Due to its high production efficiency and easy automation, resistance spot welding has become the most important welding method in the production of household appliances. The traditional ordinary low-carbon cold-rolled steel plate has good spot welding performance, and the spot welding quality problem is not prominent. With the customer's requirements on the corrosion resistance of products, hot-dip galvanized steel sheets with good corrosion resistance are widely used. [0003] Compared with ordinary low-carbon cold-rolled steel sheets, the spot welding of galvanized steel sheets has two main differences: one is that the melting point of metal zinc is low, and...

AI Technical Summary

Problems solved by technology

The quality problem of spot welding of thick-coated galvanized steel sheets has become more prominent, which has become the main reason for restricting its use

The weight of the passivation film and the presence of anti-rust oil will increase the surface resistance of the galvanized sheet, deteriorate the electrical conductivity, reduce its welding performance, cause problems such as welding spatter and blackened solder joints, and reduce the welding window.

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