Choosing spring steel for performance and environment
Spring material affects the design, but no grade is the right choice in isolation. The application, required torque or force, dimensions, cycle target, environment and cost all need to be considered together.
Common material directions
Common options include 65Mn and 62Si2MnA spring steels, SK5-grade or SAE 1078-grade high-carbon spring steel, SUS301 stainless spring steel and SUS201 stainless steel. Exact grade, condition and availability should be confirmed for each project. SK5 or SAE 1078 grade should not be described as imported unless the specific supply can be documented as imported.
Consider corrosion exposure
Carbon or alloy spring steel is often a cost-effective choice for general industrial conditions. Protection may depend on rust-preventive oil, packaging, storage and the final product enclosure. SUS301 offers better moisture and corrosion resistance, but it is not completely corrosion-proof. Chloride, salt-spray, chemical or other severe exposure needs evaluation against the actual environment and test requirement.
Confirm by application and validation
Material substitutions can change the spring’s output and durability. Review the material together with thickness, width, geometry, heat treatment and operating stress. Where the project has a defined life or environmental target, agree on the test method and acceptance criteria before approving the design.
A drawing or sample plus the operating environment and target performance gives the engineering team a more reliable basis for recommending a material direction.
