In order to reliably protect the metal from negative corrosion processes, a primer must be applied. This composition may have a different purpose.
Varieties of primer
The primer for the metal is selected depending on the external conditions that will be maintained during operation, as well as on the type of surface. Thus, the primer can be designed for application to non-ferrous or ferrous metals. Among other things, this composition can be designed to convert rust. There are phosphating, passivating, isolating, inhibitory and protective mixtures.
Phosphating mixtures are bicomponent substrates which are made from phosphoric acid and a diluent. You can use such a mixture for all types of metals. It improves grip.
The insulating primer is still alkyd or epoxy. It is intended to protect the surface from moisture and oxygen. In its composition - iron minium, zinc white, as well as fillers. This composition is used most often for ferrous metals.
Passivating primer for metal
It is able to reduce electrochemical characteristics. Helps slow down corrosion. If we talk about the inhibitory mixture, then it forms on the surface a new kind of material by the type of enamel-soil, which combines the properties of two compositions. The inhibitors that make up its composition can be aqueous or oil soluble.
Tread primer
It is designed to work with rusty surfaces. If you need a primer for metal, then you can choose the above, it consists of an alloy of magnesium with zinc, as well as lead powder. An invisible film is created on the surface after application, which is capable of protecting the metal base even when scratches occur. This was achieved thanks to the particles of zinc, which are part of the primer. Quite often there is a need to treat a surface that has already been subject to rusting processes. There are also such primers, their application is carried out after surface cleaning. After the base becomes protected from moisture.
Features of selection and application
If you need a primer for metal, you must first familiarize yourself with the criteria by which the selection is made. It is important to consider not only a variety of metal, but also climatic as well as mechanical stresses. After that, the master should familiarize himself with the technology of applying the composition. Initially, the surface should be freed from the old coating, cleaned of dirt and dust, and also leveled. Among other things, it is necessary to carry out degreasing, as well as eliminate rust.
The rust primer for metal should be applied with the appropriate tools, it can be a brush, pneumatic sprayer or roller. If the second option is used, then the work can be completed in a shorter time, however, such equipment is not always in the arsenal of the master, and it is not advisable to rent it to cover small areas. When buying materials, it is important to take into account consumption, on average, this figure varies from 120 to 140 grams per square meter. This is true for applying two coats. It is this number that is recommended by the manufacturer.
Moisture-proof coating is often applied on top, especially for metal primers, which will be exposed to frost and snow. Whatever primer is applied, humidity and temperature conditions must be observed. As for the last range, it can vary from -10 to +25 degrees.
Features of alkyd primers for metal
Metal alkyd primer can be used as an independent coating. The advantage of this composition is that it is not necessary to apply paint or enamel on top of it. Among the additional advantages, it is possible to provide excellent anti-corrosion characteristics, as well as the ability to be applied to a surface that has been subject to rusting processes. Thus, this indicates that the alkyd primer acts as a transducer. The mixture is able to provide reliable protection against various weather phenomena with regard to ultraviolet radiation, as well as temperature extremes.
This composition has a high hiding power. Due to the fact that among the ingredients of alkyd protection there is an aluminum filler, the described material provides additional wear resistance.
Overview of primers and their prices
If you need to purchase a primer, first you should familiarize yourself not only with the prices, but also with the manufacturers. For example, a primer brand LACRA will cost 2,000 rubles, this amount you will have to pay for 20 kg of the mixture. It has excellent quality characteristics and is able to protect metal from external influences. By purchasing a Super composition with the same volume, the consumer will have to pay 1170 rubles. By covering the surface with this mixture, you protect it and extend the life of the product. If you need to cover a surface of a smaller area, then you can buy a mixture of the first mentioned brand in the amount of 1 kg, in which case you will have to give 120 rubles to a building materials store. Dufa brand material costs 1,600 rubles for 2.5 liters. As for the manufacturer, HAMMERITE, it presents for sale a primer for 1150 rubles. The can will have a volume of 0.75 liters.
Conclusion
The described compositions vary in purpose and operating conditions. For example, a primer for metal for a car has corresponding characteristics. However, there are universal mixtures, they are suitable for standard surfaces and for problem areas. Among the former, cast, forged, and other products can be distinguished, which have a slight roughness that improves adhesion, which is very good for priming. Among the problematic bases are copper, aluminum, galvanized metal, as well as any other materials that can give a chemical reaction on the surface and reduce adhesion.
If you will purchase a primer for metal GF 021, then you need to familiarize yourself with the manufacturer's recommendations. So, the bank may indicate the time during which the composition is able to hold on to the metal. Corrosion-resistant features of the composition are also important. All the mentioned characteristics must be paid special attention before purchasing materials. The durability of the protective coating and the life of the metal itself will depend on this. It is not necessary to save on the primer mixture, it is better to purchase goods from the manufacturer who has established itself in the market of relevant materials.