Material Strength

[noctorum]

Aluminum is stronger than forged iron, forged iron is stronger than cast.

Correct?

[RandomTask]

This answer can not be answered in a definitive "Yes" or "No". I'm assuming that even though you said Forged Iron, you mean Forged Steel. Iron is rarely used in anything automotive. Although it has a high strengths, it is extremely brittle and will crack/stress fracture easily. Forged almunium is generally not as strong as forged steel but is a lot lighter.

This website gives a nice summary on the different strengths and characteristics
http://www.63xc.com/scotn/metal.htm

This website gives specific numbers:
http://www.thedirtforum.com/materials.htm

More detailed information can be found by going to a library and researching "metallurgy" for about 30 min. I would def reccomend taking some time doing this if you plan on any modifications as most cars are, (you guessed it) based on metals and alloys.

Joe

[Reed]

actuall iron is used quite extensively in engine blocks.

[beyondloadedSE]

Material--------------------Elastic Strength tens. (ksi)---- Ultimate Strength tens. (ksi)
Wrought iron----------------------30--------------------------48
Cast iron - malleable---------------32--------------------------50
Cast iron - nodular-----------------70--------------------------100
Aluminum Cast, 195-T6-------------24--------------------------36
Aluminum wrought, 2014-T4--------41--------------------------62
Aluminum wrought, 2024-T4--------48--------------------------68
Aluminum wrought, 6061-T6--------40--------------------------45
Steel SAE 4340--------------------132-------------------------150

Heres just a few out of my strength of materials book.