Allowable Bending Stress for Grey Cast Iron

That depends on the strength of the Iron. Since GCI has no elongation (to speak of) The yield strength is the same as the tensile strength. For each class of iron there is a minimum spec given. I dont know the modern designations you can find a great paper on GCI here:


I would use a high factor of saftey or maybe consider using another material. With no ability to deform GCI fails catastophically.

Nick

I agree with Nick E. Cast iron for a structural application. Scary. I would never even consider it.

DPA

Principally used in castings, wide range of mechanical / physical properties, i.e. tensile strength from 20 KSI to over 200 KSI
See:

Check this reference out by using the URL below.

Gray and ductile iron castings handbook; including data on gray, ductile, white, and high alloy irons
•• By: Charles F Walton
•• Publisher: Cleveland, Gray and Ductile Iron Founders' Society, 1971

Wouldn't you want a material that has more forgiveness to it?

Something with a nice, stretchy quality. Do you live in an earthquake zone? Trick question. My physics professor used to say everywhere is an earthquake zone.