for garden objects
Stainless steel - high-grade material for metal garden objects
Steel types under the term “stainless steel” have a high corrosion resistance. The reason for this is the protective film formed on the surface by the chemical composition which is called “passive layer”. Non-oxidizing steel has a unique ability: it is self-healing. On the basis of its alloy content it develops an extremely thin, transparent passive layer on the surface. Even if the non-corroding steel is being scratched or damaged, it instantly develops this passive layer under the influence of oxygen in the air or in the water again. That is why stainless steel does not need any coating or other forms of surface protection.
But a certain amount of care must also be given to the stainless steel surface to maintain a good visual appearance.
Bench substructure made of stainless steel, seat rest made of black plastic
“Stainless steel” does not always equal “stainless steel”. For outdoor purposes and in nearly all cases Gartenmetall® uses the especially high-graded and corrosion resistant stainless steel with material number 1.4404 (V4A). Compared to the common stainless steel (V2A) this stainless steel has got an increased resistance towards chloride, acids and sulphur dioxide. Basically we do not recommend the use of chloride-containing water admixtures e.g. for reducing water turbidity, as it can – if used intensively – lead to extra strain and corrosion of the material.
In general Gartenmetall® can deliver all surfaces. Well-known surfaces are brushed or grinded. Daily use in the GaLaBau has shown that “rotex-grinded” surfaces are particularly well suited for garden objects. Because of the undirected polish the sunlight is broken evenly and fingerprints are hardly invisible. And the most important advantage: Scratches, that are caused by installation or use, can be removed easily and without loss of quality on site.
Rotex-grinded Gartenmetall®-stainless steel
Attention: Handling of stainless steel
Stainless steel (V2A and V4A) can oxidize at the surface because of adhering external iron particles. These particles can come to the surface e.g. by touching the steel, by rust particles from nearby patina surfaces or by abrasive cutting. If the rust particles have not been on the stainless steel surface for very long, they can normally be removed with a simple kitchen sponge. But if the particles have already rusted into the surface then we recommend the use of special steel cleaners as we offer them.
Maintenance cleaning with surfaces made from stainless steel
In the case of outdoor installation, the cleaning effect of the rain is generally sufficient to remove harmful deposits on the surfaces. But surfaces that are not reached by rain require maintenance cleaning. A dishwashing detergent is usually sufficient to remove fingerprints. For maintenance cleaning and care of stainless steel, especially to clean organic and greasy dirt, the mild and milk-like STAINLESS STEEL CARE on alkaline basis is recommended.
Scouring powders are unsuitable as they scratch the surface. Very oily and greasy dirt can be removed with alcohol-based cleaning products e.g. methylated spirits, isopropyl alcohol or acetone which are harmless to stainless steel. Mortar and cement splashes can be removed with warm, diluted phosphoric acid. Then rinse abundantly with neutral, ideally demineralized water. Alternatively vinegar which is diluted with water is also suitable. It just depends on the level of dirt. The same polishing pastes that are used for chrome-plated parts are suitable as supplementary care for stainless steel surfaces.
for maintenance cleaning
Cleaning for persistent stains
A remarkably strong stainless steel cleaner is our Gartenmetall® product STAINLESS-STEEL-LOTION. When the product is applied, the surfaces are cleaned, visually brightened and treated with a sealant at the same time. It should not be used for the “normal” maintenance cleaning of stainless steel as the surface is processed sharply.
STAINLESS-STEEL-LOTION for removing corrosion stains on stainless steel
Visible rust stains on stainless steel
before the treatment.
After the treatment the rust stains are gone.
Suggestion for tender template
“High-quality stainless steel, material number 1.4404, AlSI 316L (V4A) or of equal value, material properties according to DIN EN 10088 – 2. Surface of visible sides rotex-grinded up to sample. All welds stained and passivated.”
Merkblatt 965 – Reinigung und Pflege von Edelstahl-Rostfrei im Bauwesen (Informationsstelle Edelstahl Rostfrei, 2009)
for basic material