Selection of stainless steel for facade anchoring systems
Proper design of a substructure for facade installation requires a suitable solution and the right material for the anchoring element. It is very important to select the right steel grade for the anticipated operating conditions.
According to standard EN 10088, austenitic steel is divided into grades: 1.4301, 1.4305, 1.4306, 1.4307, 1.4310, 1.4401, 1.4435, 1.4436, 1.4438, 1.4439, 1.4529, 1.4539, 1.4541, 1.4547, 1.4550, 1.4571. Ferritic steel: 1.4000, 1.4003, 1.4016, 1.4510. Martensitic steel: 1.4006, 1.4021, 1.4028, 1.4031, 1.4034, 1.4057, 1.4122. Ferritic-austenitic steel: 1.4362, 1.4410, 1.4460, 1.4462.
Corrosivity categories
Category C2, low atmospheric corrosivity. Outside: atmospheres with low levels of pollution, mainly rural areas. Inside: unheated buildings where condensation may occur, e.g. warehouses, sports halls.
Category C3, medium corrosivity. Outside: urban and industrial atmospheres, medium SO2 pollution, coastal areas with medium salinity. Inside: production premises with high humidity, e.g. food plants, laundries, breweries.
Category C4, high corrosivity. Outside: industrial areas and coastal areas with medium salinity. Inside: chemical plants, swimming baths, ship repair yards.
Category C5-I, very high industrial corrosivity. Outside: industrial areas with high humidity and aggressive atmospheres. Inside: buildings with almost continuous condensation and high pollution.
Category C5-M, very high marine corrosivity. Outside: coastal and offshore areas with high salinity. Inside: buildings with almost continuous condensation and high pollution.
Which grade to choose
Basic chromium stainless steels with a ferritic structure have good corrosion resistance in internal applications, except in extremely aggressive environments such as a swimming pool hall. The commonly used austenitic chrome-nickel steel grades 1.4301 and 1.4307 according to PN-EN 10088-1 can be used for internal and external components exposed to an atmospheric environment of corrosivity category C3 according to PN-EN ISO 9223.