Preparation method of tin-plated plate and application of tin-plated plate prepared by preparation method

Abstract

The invention provides a preparation method of a tin-plated plate and an application of the tin-plated plate prepared by the preparation method. The preparation method comprises the following steps that a strip steel sequentially undergoes tin plating, soft melting, passivation and oil coating to obtain a finished product, wherein in the tin plating process, the current density of the first pass and the last pass is 10-20 A / dm<2>, and the current density of the middle pass is 5-10 A / dm<2>, in the soft melting process, a pure induction soft melting process is adopted, the temperature of soft melting is 240-245 DEG C in the soft melting process, the soft melting time is 0.5-1.5 s, and in the passivation process, a sodium dichromate solution with the concentration being 27-31 g / L is used as apassivation solution. Through the preparation method, the tin-plated plate which is uniform in coating, good in welding performance, good in binding force with a PET film and extremely low in tin quantity is prepared, and the tin-plated plate can be used for replacing a chromium plated plate to be applied to the coated iron.

Description

technical field [0001] The invention belongs to the technical field of iron and steel smelting, and in particular relates to a preparation method of a tinplate and an application of the tinplate thus prepared. Background technique [0002] As a revolutionary innovation in the field of metal packaging, coated iron has received great attention. At present, most of the substrates for coated iron are chrome-plated plates. Chrome-plated plates have advantages over tin-plated plates in terms of manufacturing cost and bonding force with PET films. However, the welding performance is poor, and it is only widely used in top and bottom covers and two-piece cans. However, the technology of applying tin plate instead of chrome plate to coated iron is not mature at present, and the specification range of tin coating amount of conventional tin plate is generally 1.1g / m 2 ~11.2g / m 2 , while the amount of tin plating is less than 1.1g / m 2 The application of ultra-low tin products is stil...

AI Technical Summary

Problems solved by technology

[0002] As a revolutionary innovation in the field of metal packaging, coated iron has received great attention. At present, most of the substrates for coated iron are chrome-plated plates. Chromium-plated plates have advantages over tin-plated plates in terms of manufacturing cost and bonding force with PET films. However, the welding performance is poor, and it is only widely used in top and bottom covers and two-piece cans

However, the technology of applying tin plate instead of chrome plate to coated iron is not mature at present, and the specification range of tin coating amount of conventional tin plate is generally 1.1g / m 2 ~11.2g / m 2 , while the amount of tin plating is less than 1.1g / m 2 The application of ultra-low tin products is still rare, and there are mainly problems such as uneven tin plating and alloying of pure tin and base iron in the reflow process section during the production process of ultra-low tin tinplate.