Stainless steel selection requires more than choosing a material with corrosion resistance. The grade should be reviewed against the service environment, mechanical loads, operating temperature, and machining behavior.
Common Grades
- 303: Good machinability and moderate corrosion resistance.
- 304: General-purpose corrosion resistance with balanced mechanical properties.
- 316 / 316L: Greater resistance to pitting and crevice corrosion in many chloride-containing environments.
- 420: A hardenable martensitic grade used where wear resistance or heat-treated properties matter.
- 17-4PH: Precipitation-hardening stainless steel combining high strength and corrosion resistance.
Machining Considerations
Austenitic grades can work harden, and cutting heat and chip control may affect the machining strategy. Material condition and hardness also influence tooling and achievable results for hardenable grades.
Confirming the Grade
Clearly state the grade, material condition, heat treatment, corrosion exposure, and critical dimensions on the drawing. When a grade is not finalized, provide the service requirements so suitable options can be reviewed.