Metal Types and Properties Flashcards

What is 'electrogalvanized' steel and how does it differ from hot-dip galvanized?

Answer: Electrogalvanized applies a thinner, more uniform zinc layer through electroplating; hot-dip galvanized applies a thicker coating by immersion in molten zinc

Electrogalvanized steel has zinc electroplated onto it, producing a thinner, smoother, more uniform coating. Hot-dip galvanized is immersed in molten zinc, producing a thicker coating with superior corrosion protection.

What is the significance of the 'minimum bend radius' for a particular sheet metal material?

Answer: It is the tightest bend the material can make without cracking, expressed as a multiple of material thickness

Minimum bend radius (often expressed as a multiple of thickness, like 1T or 2T) is the tightest bend a material can make without cracking on the outside of the bend. It varies by material, temper, and grain direction.

What is 'PVC-coated galvanized steel' and what is its typical application?

Answer: Galvanized steel with a factory-applied vinyl coating for enhanced corrosion resistance in swimming pool and coastal environments

PVC-coated galvanized steel has a factory-laminated polyvinyl chloride film on one or both sides. It provides excellent resistance to moisture and chemical corrosion, commonly used for pool dehumidification and coastal HVAC ductwork.

What is 'Muntz metal' and how is it related to sheet metal work?

Answer: A type of brass (60% copper, 40% zinc) used for architectural sheet metal, hardware, and marine applications

Muntz metal is a brass alloy containing approximately 60% copper and 40% zinc. It is harder and stronger than standard brass and is used for architectural panels, marine fittings, and decorative sheet metal work.

What is the purpose of 'passivation' of stainless steel after fabrication?

Answer: To chemically treat the surface to restore and enhance the protective chromium oxide layer after welding or fabrication

Passivation uses acid solutions (typically nitric or citric acid) to remove free iron particles and contaminants from the stainless steel surface, allowing the chromium oxide protective layer to reform and provide maximum corrosion resistance.

What is the approximate weight per square foot of 24-gauge galvanized steel?

Answer: 1.156 pounds

24-gauge galvanized steel weighs approximately 1.156 pounds per square foot. This weight factor is essential for calculating duct system weights, determining hanger requirements, and structural load calculations.