Maximizing Precision When cnc machining part Stainless Steel

Stainless steels are engineered alloys offering strength, corrosion resistance, and aesthetics suited for many industrial applications. However, their enhanced properties also make them more difficult to machine compared to carbon or alloy steels. Here are some best practices for CNC processing of stainless parts.

Understand Material Grades

The five most common stainless grades - 200, 300, 316, 17-4PH and HASTELLOY - each have varying machinability based on chromium, nickel and molybdenum content. Slower feeds and speeds are required compared to alloy or mild steels.

Select Appropriate Tool Coatings

For prolonged tool life, vapor-deposited coatings like titanium nitride (TiN) and aluminum titanium nitride (TiAlN) help reduce built-up edge and friction temperatures during milling or turning. Indexable inserts should be chosen to match material hardness.

Use Rigid cnc machining part Configurations

Stainless requires greater chip control due to work hardening tendencies. Rigid machine setups with sturdy fixtures and clamping minimize vibration to promote chip evacuation and extend tool durability.

Take Shallow Cuts at Lower Speeds

Roughing stainless demands a lighter depth of cuts at slower spindle RPMs - typically half those used on mild steels. This incremental material removal alleviates cutting loads and attendant work hardening.

Optimize Chatter Prevention

Techniques like using a variable pitch threading tool, wider inserted tools, or fine finishing passes can counter chatter which causes loss of tolerances and surface finish fidelity on stainless parts.

Confirm Cleanliness After Machining

Stainless is sensitive to work hardening defects and potential corrosion if excess chips or other contaminants remain. Thorough post-process clean-up ensures each part's full integrity.

Consult Experienced Stainless Machinists

For complex parts, advanced processes like multi-axis Swiss turning or EDM may be better suited than conventional milling/turning. Expert fabricators optimize method selection for ideal stainless CNC machining results.