Re “Cold Galvanizing” coatings. See catalog page 1947 at
The coatings conform to
MIL-P-21035B PAINT HIGH ZINC DUST CONTENT, GALVANIZING REPAIR, which makes them zinc-rich paints rather than “galvanizing” IMHO.
Better corrosion resistance than with
MIL-P-21035B paint can be obtained with Dacromet®. This could be considered a “Warm Galvanizing” coating or more properly “Warm Galvalume,” since it also contains aluminum. From
“Our coating compositions are proprietary water based coating dispersions containing metal oxides, metallic zinc and aluminum flakes. The zinc and aluminum platelets align in multiple layers forming a metallic silver gray coating. Applied as a liquid material, the coating becomes totally inorganic after curing at 610° F/321°C.”
As the cure temperature is only 51
oC below the Al-Zn eutectic, and especially with some proprietary additives present, I would expect some significant sintering during the cure.
In addition to the “cold galvanizing” field repairs of HDG mentioned by
JStephen, there are also hot methods for applying molten zinc to a cleaned surface: Thermal spray is used for large areas and “hot stick” for small. The latter is essentially soldering: heating a fluxed area with a torch and then applying stick zinc alloy such as Galvaguard®. For more information, Industrial Galvanizers' website is very informative on HDG, and also compares the various types of zinc coatings: