Materials

Steel vs aluminum compared: weight, strength, stiffness, corrosion, welding and cost, with a worked 8-inch beam example showing why aluminum must be bigger.

Yield strength of steel explained: what Fy means, how it differs from tensile strength, how it is tested, and minimum values for A992, A572, A500, A53 and A36.

Is stainless steel magnetic? 304 and 316 are not when annealed, but ferritic, martensitic and duplex grades are. Why cold work and welds change the answer.

Galvanized steel is carbon steel coated in zinc to stop rust. How hot-dip and sheet galvanizing work, what G90 means, and where galvanized steel fits best.

What is steel made of? Iron, under 2% carbon and about 1% manganese, plus alloys like chromium and nickel. How it is made in the US and what each element does.

Steel melts at about 2,800°F (1,500°C), but fire weakens it far sooner. Melting point vs fire temperatures, why the WTC steel did not melt, and fire protection.

Mild steel is low-carbon steel with about 0.05 to 0.25% carbon. See its properties, the real grades behind the name, common uses, and when to specify A36.

Is titanium stronger than steel? Compare real ASTM grades: yield strength, strength-to-weight, stiffness, cost and corrosion, and why buildings still use steel.

A36 steel explained: 36 ksi minimum yield, 58-80 ksi tensile, what it is used for, how it compares to A992 and A572 Grade 50, and what to ask for when ordering.

Yes, galvanized steel is magnetic. Why the zinc coating does not stop a magnet, how magnetic gauges measure it, and how to tell galvanized from stainless.