Manufacturing method for hot dipped steel plates excellent in blackening resistance and corrosion resistance

A manufacturing method, hot-dip plating technology, applied in hot-dip plating process, manufacturing tools, heat treatment furnace, etc., can solve the problems of low solubility, long time, coarsening of coating structure, etc., achieve uniform distribution, less color difference, good The effect of blackening resistance
CN108690944AActive Publication Date: 2018-10-23武汉钢铁有限公司
9 Cites 8 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
武汉钢铁有限公司
Publication Date
2018-10-23

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a manufacturing method for hot dipped steel plates excellent in blackening resistance and corrosion resistance. The manufacturing method comprises the following steps: increasing the oxygen partial pressure in an annealing furnace to 30-80 ppm when basic strip steel enters a preheating section of the annealing furnace, wherein the dew point of the preheating furnace is 0-50DEG C, the furnace pressure of the annealing furnace is 300-500 Pa, and the preheating temperature is 500-700 DEG C; controlling the dew point of a soaking section at 30 DEG C below zero to 30 DEG Cafter the basic strip steel enters the soaking section, wherein the hydrogen content in percent by volume is 15-25%; and finally, controlling the cooling speed at 20-100 DEG C / s for cooling, wherein the basic strip steel enters a zinc pot to produce Mg-containing hot dipped steel plates. Mg-enriched ternary eutectic phase sheets in coatings of the steel plates are small in interlayer spacing, relatively short and uniform in distribution, Mg-containing oxides are unlikely produced, and the hot dipped steel plates have high corrosion resistance and good blacken resistance. In a severe environment, the corrosion resistance of the coatings is 2-3 times of that of conventional hot dipped steel plates, or the corrosion resistance is even higher, and the quality of the surface tissues of the coatings is good.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of hot-dip galvanizing, in particular to a method for manufacturing a hot-dip galvanized steel sheet with excellent blackening resistance and corrosion resistance. Background technique

[0002] Galvanizing is the most common and effective method for steel anticorrosion. However, with the continuous improvement of the requirements for the corrosion resistance of steel products, hot-dip pure galvanizing has gradually been unable to meet the requirements. Adding a small amount of Mg element in the Zn-Al alloy coating can greatly improve the anti-corrosion performance of the zinc-based coating. Hot-dip Zn-Al-Mg alloy coating has broad application prospects due to its good corrosion resistance and damage resistance.

[0003] Blackening is a prominent problem that may exist in galvanized steel sheets, especially in Mg-containing coatings. The reasons mainly include the following points: 1) the anodic active diss...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More