Hot dip galvanizing is a method of coating anti-corrosion of steel by immersion in a bath of molten zinc (450 °) which gives it a thick coating (60 to 100 μ / side) * unlike plates precoated zinc continuously (5 to 20 μ/ side) which is cut or welded after coating.
(* 1μ (micron) = 1/1000th mm)
The zinc coating on the finished product helps protect the edges and welds. Moreover The product becomes sealed, hence the interest of this technique for watering cans, buckets and other containers.
Zinc is one of the best protection against corrosion of steel (prevents rusting). Almost half of world production is used to protect steel (in the automotive, construction, household appliances, industrial equipment, ...).
Its effectiveness over time is assessed according to the thickness of the coating and the environment in which it is exposed.
Rural atmosphere: loss of 0.8 to 1.5 microns per year
Urban atmosphere: loss of 1.5 to 3 microns per year
Marine atmosphere: loss of 2.5 to 5 microns per year
Hot dip galvanizing therefore ensures durability of steel of about 30 years in an atmosphere of average aggressivity.
On cooling, the zinc crystallizes. It reveals a nice "fleurage", enjoyed in decoration.
Zinc is a metal density of 7.13. This is the 24th most abundant element in the terrestrial crust. The main ore, the sphalerite, is located primarily in Australia (21%) and China (17%). This is a metal used since antiquity. Zinc bracelets dating from 500 BC have been discovered in Greece.
Zinc is an essential element for humans. They are zinc deficiency in populations prone to malnutrition or for those who eat unbalanced way.
Zinc is known for its good fungicidal properties and antiseptic. It is used in the treatment of acne and between, say in the composition of Mitosyl * (* Sanofi-Aventis) used against the redness of the buttocks of the infant.
It is probably this characteristic that allows the water in our drinkers for animals not to "wallow" in contrast to plastic troughs.
Zinc is a dietary supplement rather fashionable for its effects on skin and hair. He is credited with a beneficial effect on sexuality. However, zinc has a high solubility in contact with acidic foods and the use of zinc in contact with food is regulated in some countries. The council of Europe Guidelines (oct.2000) state that "Zinc galvanised utensils can be used in contact with dry foodstuffs and with non-acidic foodstuffs"
By reacting with ambient elements (moisture, oxygen, ...), zinc becomes ash-grey and patined, its luster and fleurage disappear. In contact with standing water, it forms whitish spots (sometimes called "white rust"), constituted in particular with hydroxide and zinc oxide. It's sometimes sought for the aspect "aged" or "vintage".