Effect of Heat Treatment on Modulus of Rigidity and Damping Decrement in Torsion of Cold-Drawn Wire
(All results from torsion pendulum at about 1 cps)
After heat treatment, alloy X-750 springs will have a thin oxide coating. This oxide is beneficial in aiding resistance to many corrosive environments
and need not be removed. Pickling after precipitation treating may cause an acid attack on the grain boundaries or result in pitting.
Removing the oxide by mechanical means lowers relaxation resistance.
When possible, springs should be used with the oxide on. If they must be cleaned, treatment in a reducing bath (sodium hydride) followed by water quenching
and rinsing gives a good surface.