A composite electroplating method for crystallizer copper tube with elemental nickel transition layer

Abstract

The invention discloses a method for composite electroplating of a crystallizer copper tube with an elemental nickel transition layer. The method comprises first electroplating a nickel layer on the inner wall of the copper tube, and then electroplating a chromium layer on the nickel layer, wherein the The plating solution composition of the nickel plating layer is: nickel sulfamate 500-600g / L, nickel sulfate 25-35g / L, sodium lauryl sulfate 55-65g / L; the plating solution composition of the chromium plating layer is: chromic anhydride 140 -150g / l, sulfuric acid 1.0-1.2g / l, chromium sulfate 5-7g / l, formic acid 3-5g / l, sodium sulfate 6-8g / l; the process of the nickel plating layer is: pH4-6, plating The liquid temperature is 45-55°C, the cathode current density is 4.5-6.5A / dm2, and the immersion plating time is 10-20min; 44‑48A / dm2, plating time 30‑40min.

Description

technical field [0001] The invention relates to the technical field of electroplating, in particular to a composite electroplating method for a crystallizer copper tube with an elemental nickel transition layer. Background technique [0002] The mold is an important part of the continuous casting machine in the smelter, and the mold copper tube is an important part of the mold. Since the high-temperature molten steel flows directly through the mold copper tube, in order to stabilize the continuous casting process and ensure the safety of equipment and operators, the mold copper tube is required to have good high temperature resistance, wear resistance and corrosion resistance. The crystallizer copper tube with hard chromium plating is produced by chrome plating on the inner wall of the copper tube, because the high temperature resistance, wear resistance and corrosion resistance of the mold copper tube can be greatly improved, and the production process is simple, high in ef...

AI Technical Summary

Problems solved by technology

Although this patent application has paid attention to the problem of plating peeling, it has also adopted an appropriate solution, that is, the method of using a transition layer of chrome plating, but the transition layer is still chromium, and it still does not fundamentally solve the two different problems of chromium and copper. The peeling problem caused by the material difference, so its use effect is still not very ideal

[0004] CN1465753A also discloses a method for electroplating the inner surface of a crystallizer, which adopts a nickel-cobalt alloy as a transition layer, although it also solves the problem of material performance differences between chromium and copper, but because it adopts an alloy coating, the composition of the plating solution is complicated, and the electroplating process The requirements are high, and the alloy composition of the alloy coating is not temperature-sensitive, so it is not easy to control the consistency accurately, so there are also defects of inconsistent and unstable coating

[0005] In the prior art, there are also reports on the use of alloys composed of nickel and other metals as the transition layer, but similar to the above-mentioned patents, complex alloy plating solutions need to be configured, the requirements for electroplating process control are high, and the coating is unstable and inconsistent

In the prior art, there is no report that only nickel is used as the transition layer