Mechanical Properties for various things

They all need to be soft stringy and taste really nice.

Too many variables. There's no way to say without understanding the context for any of the items mentioned.

I prrrrrrrrrrr-furred my answer!

Prrrrrreferably, they should all be made by Purina.

At the risk of being serious..dunno why...must be bored.

Elevator cable and piano wire both need same properties...eg withstand a lot of tension.

Leaf spring...c'mon...maybe it needs to be springy?

Coat hanger ...cheap as possible easy to form, plated so it doesn't rust and mark clothes.

Paperclip, as above but springy.

Bracket for book case ,as per coat hanger.

Staple similar to paperclip but a tad softer.

Gas turbine blade...now that's the one that really has to be floppy and taste nice....suggest you look it up yourself.