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Is it possible to have steel with chemistry too good for galvanizing?

It is possible to have steel chemistry with levels of silicon and phosphorus that are too low to meet the minimum thickness levels specified in ASTM A123 and ASTM A153. Very low silicon levels are seen more often on pipe though, not plate because aluminum is sometimes used as a deoxider rather than silicon. For steel with very low levels of silicon and/or phos...
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Galvanizing small parts, hardware, and fasteners to ASTM A153

ASTM A153 governs zinc coatings applied by the hot-dip process on iron and steel hardware, including nails, bolts, nuts, fasteners, and rods.  The hot-dip galvanizing process for articles galvanized to ASTM A153 is identical to the process required under ASTM A123 with the exception the iron and steel hardware in ASTM A153 are centrifuged or...
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Clogged Holes

Clogged holes are a defect caused by molten zinc metal not draining adequately and partially or completely filling holes with excess zinc. Molten zinc will not drain easily from holes less than 3/10” (8mm) in diameter due to the viscosity of zinc metal. A good example is the screen shown to the right. Clogged holes can be minimized by making all holes a...
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Clogged Threads

Clogged threads are caused by poor drainage of a threaded section after the product is withdrawn from the galvanizing kettle. Clogged threads, as seen to the left, can be cleaned by using post-galvanizing cleaning operations such as a centrifuge or by heating them with a torch to approximately 500 F (260 C) and then brushing them off with a wire brush to remove the excess zinc. The
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Is there concern about galvanic corrosion when different types of zinc-coated steel are in contact?

There is not a concern of dissimilar metals corrosion (galvanic corrosion) when pairing zinc-coated steel of different types (for example when pairing a hot-dip galvanized bolt with a mechanically galvanized nut). Please be aware, however, that different zinc coatings offer different corrosion protection and service lives...
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