Galvanic bath with your hands. Lining and heating of galvanic baths

Familiar to all words "gilded", "silvered", "chrome" or "nickel-plated" already firmly entered the lexicon of modern man and are perceived by them almost automatically. Nobody even thinks that behind all these words lies the technology that allowed a person to reach the modern level of civilization - galvanics.

Galvanics - what is this process?

Electrochemical process, in which under the influence of electric current there is a precipitation of metals on the selected surface, is called galvanic engineering. Such a process can be applied to any object, even to non-metal. This was the decisive factor for the wide application of galvanic engineering in various industries. With it, you can gild, silver, nickel and chrome any objects, ennobling their appearance for decorative purposes or changing the physical and chemical properties of the surface in purely practical (for increasing wear resistance, increasing resistance to corrosive environments, etc.). The equipment is a galvanic bath.

Types of electroplating

There are two types of this technology, which have become widespread not only in many branches of modern industry, but also at home. The first - electrotype - has as its goal the creation of exact copies of the surfaces of the object from the metal deposited on them. The second, the most common in everyday life, and in production, is to create a thin - no thicker human hair - covering the entire surface of the object and is called electroplating.

What is a galvanic bath?

Since galvanic processes occur due to electrolysis, it is natural that electrolytic solutions and special mechanical and electrical equipment are used. Galvanic baths are a combination of all of the above components of the process, but the main components to which increased demands are the solution (electrolyte) and the container for it. This is especially important if you are talking about the use of electroplating or electroforming in the home.

To the electroforming tanks, there are increased general requirements, which, despite the fact that there are many types of these containers, all of them must strictly correspond. They must be sealed and chemically neutral to the solution used, capable of maintaining the required thermal conditions (heating of galvanic baths and their cooling must be controlled), and also convenient and safe to maintain. Baths are made of different materials.

Methods for analyzing galvanic baths

Thanks to modern developments, new opportunities for analyzing the electrolyte used in the electroplating process have appeared. This is necessary for a qualitative result of the process, obtaining a more uniform and durable coating. Analysis of galvanic baths in modern conditions can be carried out using chemical and physicochemical methods. In the second case, photometric studies, polarographic, ampero- and potentiometric methods are used, which give better results in determining the composition of the electrolyte.

Protection of galvanic tanks

One of the problems of galvanic processes is the protection of the electrolyte tanks from the destructive effect of the solution (acidic or alkaline) in which electrolysis proceeds. If the bath is made of a neutral material, for example, plastic, then there is no problem. But this is possible only in cases with small volumes. If you take industrial plants, then in galvanic plants, solution tanks are made of metal. In this case, there is a need to protect them from:

- contact with the solution, which provides a longer service life;

- corrosion of metal, creating unnecessary impurities in solution;

- distortion and changes in the electric field.

Such protection can be provided by the lining of galvanic baths, carried out by sheet polymeric materials by means of hot air welding.

Making galvanic baths at home

There are many people who want to have a galvanic in their house or garage. But it should be noted that this process is unsafe. Harmful and explosive fumes, caustic and even poisonous solutions, the use of electricity make it difficult from a safety perspective. But for simple works, such as copper plating, chrome plating, nickel plating of small items, a galvanic bath can be assembled from improvised means. And even in this case, several important requirements must be observed:

- the solution tank must be rigid, chemically neutral and dielectric;

- exhaust ventilation is mandatory;

- the availability of a sufficient amount of clean water - the simplest process requires the use of about five washes;

- availability of capacity and means for neutralization of waste solutions and wastewater.

The simplest version of a galvanic bath can be made from a plastic canister, cutting off the lid with a neck and reinforcing the sides with reinforcing material. Then, on the walls of the tank along the cutting line, it is necessary to put on window or automobile gaskets. The next step is to attach the lid with piano loops to one side of the canister and fasten the latches to the lid and tank wall from the opposite side. The neck in the lid is connected to the hose for removing vapors from the outside - the simplest exhaust ventilation.

Now it remains to make three holes for the contact rods at the top of the container along the cutting line. It is desirable to make rods from a copper tube with a diameter of 10-20 mm, better than a thick wall. The ends of the tubes are twisted and the holes for connecting the poles from the power supply are drilled in them. On the rods placed at the edges, hang anode plates and connect to the plus of the source. A detail is attached to the central rod, which is a cathode, connected to a minus wire. Current And the voltage is selected depending on the volume of the bath.

Schemes of self-made galvanic baths

The simplest scheme of a galvanic bath includes only three operations: the preparatory, the actual galvanization process and the final treatment. The first is cleaning, degreasing, etching and polishing the object or part - preparation. The third operation allows you to bring the already covered part of the metal part to the "commodity" type by passivation, polishing, etc. Each operation must end with washing in clean and cold water. And if the parts were treated with alkaline solutions, then it is necessary to rinse first with hot water and then with cold water.

The part to be coated is connected to the negative wire of the device (cathode) and falls into the electrolyte. The positive wire is connected to the electrode from the covering metal (anode), which also drops into the solution. Electrolysis will cause the anode (+) to dissolve and metal settle on the cathode-part (-).

The importance of galvanic engineering for modern production

The galvanic bath in which the electroforming or electroplating process takes place is, on an industrial scale, both the child of progress and its propulsion. Because thanks to galvanic coatings, the characteristics of parts and mechanisms are improved, their production becomes cheaper, the highest accuracy of coupling is achieved, wear resistance is increased and anticorrosion properties are increased.