Material selection for vehicle leaf spring

[mattyboson12]

Homework Statement

I've gone though a material selection process to pick the optimum material for a rear leaf spring suspension for a vehicle (~700mm long) and I've selected the top 10 materials based on fatigue, fracture, toughness, cost, yield etc:

-Stainless steel, martensitic, AISI 440B, tempered at 316°C
-Stainless steel, austenitic, BioDur 108, 30-40% cold worked
-Stainless steel, austenitic, AISI 302, HT grade D
-Stainless steel, austenitic, AISI 304, 1/2 hard
-Aluminum, 7010, T7651
-Aluminum, 7055, T7751
-Aluminum, 7055, T77511
-Titanium, commercial purity, Grade 4
-Nickel-Fe-Cr alloy, NIMONIC 942, bar
-Nickel-Fe-Cr alloy, D-979, bar

In terms of manufacturing the materials into the shape below, which would be best?

Homework Equations

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3. The Attempt at a Solution [/B]
From my understanding, titanium is notoriously hard to manufacture so I would not choose this

 

[Nidum]

I would not have chosen any of those materials for a vehicle suspension spring .

Have a look instead at some of specially formulated steels available for spring manufacture .