Q 01/05

Roughly what is the upper limit of carbon content for plain carbon steel by weight?

A) 0.75%

B) 1.25%

C) 2.14%

D) 4.50%

Answer · why

C) 2.14%

Iron-carbon alloys above about 2.1% carbon are known as cast iron.

Q 02/05

Which element, at 11% or more, makes steel stainless?

A) Chromium

B) Manganese

C) Nickel

D) Titanium

Answer · why

A) Chromium

A hard oxide film forms on the surface and can self-heal when exposed to oxygen.

Q 03/05

Galvanized steel is coated in a layer of which metal to resist corrosion?

A) Tin

B) Zinc

C) Aluminium

D) Copper

Answer · why

B) Zinc

Carbon steels are galvanized by hot-dipping or electroplating.

Q 04/05

Which country produced 54% of the world's steel in 2023?

A) Japan

B) United States

C) India

D) China

Answer · why

D) China

American production was once centred on Pittsburgh, Bethlehem and Cleveland.

Q 05/05

Roughly how many tons of steel are produced worldwide each year?

A) 160 million

B) 600 million

C) 1,600 million

D) 6,000 million

Answer · why

C) 1,600 million

The industry accounts for around 8% of global greenhouse gas emissions.