ASTM A401 corrosion
ASTM A401 corrosion
(OP)
would a high sodium environment (salty air) cause corrosion quickly enough for a spring made from ASTM A401 (chrome silicon) to fail after a fairly small number of cycles? The springs are painted with liquid paint via a dip procedure. Any help would be great.





RE: ASTM A401 corrosion
Several questions that could help to provide a possible answer;
1. What is the condition of the paint on the surface of the spring? Does it exhibit rust spots or is it peeling? How long was the spring in service?
2. What is the geometry/dimensions of the spring? Coil or is it a leaf spring or some other design?
3. Can you describe the appearance of the failed end of the spring?
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
As TVP stated, the environment can play a big role in contributing to the failure. However, the lack of coverage for shot peening can also contribute to the failure. Shot peening induces local compressive stresses on the surface of the spring to reduce susceptibility to fatigue crack initiation - this is a good thing. Keep in mind however that coverage is most important during shot peening because as you introduce a beneficial compressive stress, you also introduce a residual tensile stress that could be affecting the fatigue life of the spring. Normally, the residual tensile stress occurs beneath the shoot peened surface. In your case because of uncontrolled coverage with this process, you might be introducing unwanted residual tensile stresses outside of the coverage area. If you shot peen a spring, you should provide maximum surface area coverage.
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion
RE: ASTM A401 corrosion