We use the steel grade AISI 304. It is austenitic, chromium – nickel steel that is resistant to inter-granular corrosion due to its low carbon content even without any additional heat treatment. The steel is approved for thermal stress up to 300 °C. This type of steel has excellent features and is remarkable for its high strength, excellent formability, aesthetics and the highest corrosion resistance. The steel is resistant to water, water vapor, weak organic and inorganic acids.
We prefer a brushed surface due to aesthetic reasons. We perform passivation on the final surface.
Aluminum alloy casts are cast into foundry moulds by machine or manual casting. The advantage of this technology is obtaining a form – complex and precise casting. The obtained castings are further processed and blasted.
Subsequently, the powder paint can be applied to the surface in the desired tone according to the RAL sample book. We usually use the following four tones: RAL 9006 (silver – light aluminum), RAL 9007 (silver – darker aluminum), RAL 7016 (anthracite grey), RAL 9005 (black).
Galvanized steel + powder paint
Steel – class 11 – is suitable for machining, welding, bending, and cutting. It also has the features suitable for outdoor use. We always adjust steel by applying a layer of zinc to its surface. The zinc layer is used as a protection against corrosion. Zinc protects the surface not only mechanically but also chemically. We use two methods of galvanizing. The first method is called hot dip galvanizing. It is a special dipping technique. Zinc forms a durable coating with long durability. Galvanizing is an electrolytic process when the zinc coating (anode) is electrochemically released and used on the steel parts (cathode). This creates not only an anticorrosive layer but also a visible layer with thickness from 8 to 15 µm.
The surface is subsequently treated with a powder paint in the designed color according to the RAL sampler. Our standard tones are RAL 7016 (anthracite grey), RAL 9005 (black), RAL 9006 (silver – light aluminum), RAL 9007 (silver – darker aluminum).
This several thousand – year old but still popular design material is very suitable for the production of urban furniture. Grey cast iron is used for casting of form – complex products such as side rails of benches and tree grates. Castings are always mechanically machined and blasted.
Afterwards, the powder coating is applied in the desired color tone according to the RAL sample book: Standard tones are RAL 7016 (anthracite grey), RAL 9005 (black), RAL 9006 (silver – light aluminum), RAL 9007 (silver – darker aluminum).
It is steel – a grade 11 – that is suitable for machining, welding, bending and cutting. It has suitable features for outdoor use. Steel is treated by applying a layer of zinc to its surface. The surface is used as a corrosion protection. Zinc protects the surface not only mechanically but also chemically. Hot dip galvanizing is a special plating dipping technique at the temperature of 450 – 460 °C. Zinc forms a rigid and impermeable coating with thickness from 50 to 150 µm with long durability. The coating protects steel electrochemically. It is suitable for the temperatures up to 200 °C.
The untreated glossy zinc coating exposed to weather effects naturally gets older and turns to grey patinated surface. Such a coating cannot be absolutely considered decorative. The standard ČSN EN ISO 1461, the chapter 6.1., notifies about these effects (e.g. possible formation of white rust) and states their formation must not be a reason to rejection by a customer.