Electroplating liquid for cylinder outside-tank electroplating

Abstract

The invention discloses an electroplating solution for electroplating outside a tank of a cylinder body, which comprises an electroplating solution A for pre-electroplating nickel and an electroplating solution B for electroplating a nickel-silicon carbide composite coating; the electroplating solution A contains nickel sulfate 246‑626g / L and boric acid 35‑45g / L; in electroplating solution B, nickel sulfate 246‑626g / L, boric acid 35‑45g / L, silicon carbide 10‑45g / L and electroplating additive 0.5‑2.5g / L ;The electroplating solution adopts the electroplating solution formula of pre-plating nickel and post-plating composite nickel layer, which is suitable for the electroplating process outside the tank, combined with the flowing electroplating solution to ensure the real-time replacement of cations on the coating, so that the concentration difference of cations on the surface of the cathode coating is basically zero Changes, avoiding the formation of a large concentration difference, and the change of the thickness of the coating is controllable; at the same time, the undifferentiated concentration combined with the special ratio of the plating solution ensures the compactness of the coating, avoids the appearance of loose bonding, and ensures the quality of the plating.

Description

technical field [0001] The invention relates to an electroplating solution for cylinder workpieces, in particular to an electroplating solution for flowing electroplating outside a tank. Background technique [0002] As the main part of the engine, the cylinder block is used to form the combustion chamber together with the piston and the cylinder head, and provide the movement track for the piston assembly, thereby forming a power conversion environment. When the cylinder guides the piston to reciprocate continuously, the inner wall of the cylinder and the piston rub against each other for a long time and at high frequency, which reduces the useful power of the cylinder and consumes part of the energy. Therefore, there is electroplating on the inner wall in the prior art, and the electroplating coating is used to replace the cylinder liner to solve the above problems. In the usual electroplating process, the electroplating solution is in a basically static environment, and ...

AI Technical Summary

Problems solved by technology

In the usual electroplating process, the electroplating solution is in a basically static environment, and the cations are passively moved to the inner surface of the cylinder as the cathode, and the resulting concentration difference makes the coating not tight, so it is easy to fall off, and the electroplating time is longer; and because The problem of concentration difference makes the coating thickness of the final product vary greatly and is difficult to control, which makes it difficult to control some key dimensions of the inner surface of the cylinder. Therefore, it is difficult to guarantee the quality of the finished product after electroplating

In the prior art, there is a technical scheme of circulating electroplating solution to electroplate nickel-silicon carbide composite layer on the inner circular surface of the cylinder, but because the electroplating process cannot guarantee the quality of the composite coating, the final cylinder product obtained cannot meet the needs of use; especially It is the traditional electroplating solution formula itself, which cannot be matched with the traditional electroplating process and the new process, resulting in the low pass rate of the final product and the expected service life.