Suomen Elektropinta Oy focuses on customers’ coating needs by providing carefully constructed service packages. We are happy to bring our experience along for the development of new products in our customer companies too. Read more about our coating products below, and contact us when you need an experienced coating professional in your product manufacturing process.
In Zinc Electroplating, a layer of zinc, 5-25 micrometres thick, is precipitated on the surface of a steel element with the help of an electric current. The layer of zinc is passivated with one of three options: blue, yellow, or black passivation. Another term for passivation is chromating (e.g. yellow passivation = yellow chromating).
Zinc Electroplating with blue, yellow, and black passivations are, in accordance with new environmental requirements (e.g. RoHS and WEEE regulations), processes based on trivalent chromium compounds.
On the outside, they look the same as the old coatings that were based on hexavalent carcinogenic chromium. The corrosion resistance value in trivalent passivations are almost on the same level as in hexavalent coatings, and their properties are constantly developing.
In anodising an aluminium element is oxidised through an electric current, forming a layer of 5-30 micrometres on its surface, which is then hardened by sealing. This creates a durable and decorative layer on the element’s surface.
The anodised surface can be dyed before sealing if needed. Our product range includes black anodising in addition to the natural colour (silver grey). Ask more about our special colours!
Anodising increases the durability of an element, improves its gliding properties, and finishes its appearance to meet demanding wishes as well. Anodising coating insulates elements from electrical conduction, so if electrical conductivity is important, contact points should be covered or some other coating should be selected. Anodising is a very environmentally friendly coating process as it does not involve any heavy metals or toxic chemicals.
Electroless nickel plating is a coating system that has many versions. The right version is chosen according to the required physical properties for the application in quesion. Roughly speaking, electroless nickel plating can be divided into three main categories. Low phosphorus electroless nickel plating is a crystalline coating that is hard, durable, and slick. High phosphorus electroless nickel plating, on the other hand, is structurally amorphous, and its main properties are good corrosion durability, adhesion, and mechanical strength. Medium phosphorus electroless nickel plating is situated between the two aforementioned coatings in terms of nickel content and other main variables.
Alkaline copper functions both as an independent technical coating and, most importantly, as a primer providing excellent adhesion in compound coatings. Copper has a great electrical conductivity and it also shields from corrosion. However, as a final coating copper has a tendency to oxidise, which impairs its visual properties.
Acid copper is usually coated on top of alkaline copper, where its properties (smooth surface texture and high shine) can stand out. Acid copper smoothens the surface texture and provides an excellent base for visually impressive nickel platings.
Semi-bright nickel platings harden the surface of copper, steel, zinc, and aluminium elements and shield them from corrosion. It is, most of all, a technical coating that can also be used as a final coating in certain product solutions. Usually semi-bright nickel coating is used as an intermediate coating for bright nickel or bright chromium.
Bright nickel is a decorative coating well suited to be used over copper plating and semi-bright nickel plating to add a crisp shine to the compound coating. Steel elements can also be bright nickel plated directly without intermediate coatings. Usually bright chromium is used on top of bright nickel plating so that the finished product will not be allergenic or prone to oxidation.
Bright chromium plating is usually done on top of a nickel-plated element to bring a final shine to the compound coating and to improve shine and friction properties. Chromium plating is considered a decorative coating, but it can also have very functional properties if done properly. Our facility uses a modern trivalent chromium plating process.
Salt spray tests are carried out to test and verify corrosion behaviour. In coating standards, coatings are usually given a time limit, expressed in hours, such as 720 hours in a neutral salt spray test. The most common is the NSS (neutral salt spray) test, which is done as an accelerated test in a salt spray cabinet. Elektropinta carries out standardised tests and evaluations, and delivers test reports for industrial needs.
When basic properties are not enough, and performance or visual appearance must be of a particular kind, you need to choose the right coating method, tailor the coating process, do test coatings and field tests, and analyse the results. Coating solutions can also be taken to the drawing board to receive the desired result.
Suomen Elektropinta Oy has been developing a functional coating system based on chemical nickel that can be used to fulfil all kinds of requirements from the chemical stress of process industry to hard mechanical wear.
Contact us and ask for a quote on the coating you need. We are based in Kuopio, and we serve industrial companies all over Finland.