Stainless Steel Speeds & Feeds Calculator 2026
Optimized parameters for austenitic, martensitic, duplex, and precipitation hardening stainless steels. Includes work hardening analysis and heat management.
Calculate Stainless Parameters
Stainless Steel Machining Guide
Stainless steel presents unique machining challenges. The two primary issues are work hardening (the material gets harder as you cut it) and poor thermal conductivity (heat concentrates at the cutting edge). Success requires proper technique, tooling, and parameters.
Stainless Steel Categories
🔵 Austenitic (300 Series)
Grades: 303, 304, 316, 321
Most common. Non-magnetic, excellent corrosion resistance. High work hardening!Requires positive chip load at all times.
- • 303: Free machining - easiest
- • 304: Standard - moderate difficulty
- • 316: Mo added - slightly tougher
🟣 Martensitic (400 Series)
Grades: 410, 416, 440C
Magnetic, hardenable. Better machinability than austenitic. Less work hardening but can be hard when heat treated.
- • 416: Free machining - best machinability
- • 410: General purpose
- • 440C: Very hard after treatment
🟠 Precipitation Hardening
Grades: 17-4PH, 15-5PH
High strength after heat treatment. Moderate work hardening. Machines best in solution-treated condition before age hardening.
🔴 Duplex & Super Duplex
Grades: 2205, 2507
Extremely difficult! Very high strength, severe work hardening. Reduce speeds 30-40% from standard stainless. High-pressure coolant essential.
The Golden Rule: Never Rub!
The #1 cause of problems when machining stainless steel is rubbing instead of cutting.
When the tool rubs instead of cutting, it cold-works the surface, creating a work-hardened layer that is dramatically harder than the parent material. The next pass then encounters this harder layer, causing accelerated tool wear, poor finish, and potential tool breakage.
- ✓ Maintain positive chip load - never go too light
- ✓ Never dwell - keep the tool moving
- ✓ Don't stop mid-cut - causes localized work hardening
- ✓ Use sharp tools - dull edges rub instead of cut
- ✓ Avoid interrupted cuts - each re-entry gets harder
Recommended Cutting Parameters
| Grade | Milling (m/min) | Turning (m/min) | Drilling (m/min) | Difficulty |
|---|---|---|---|---|
| 303 | 100-200 | 140-260 | 40-80 | Easy |
| 304/304L | 60-130 | 80-160 | 25-55 | Moderate |
| 316/316L | 50-110 | 65-140 | 20-50 | Moderate |
| 17-4PH | 40-90 | 50-120 | 16-40 | Difficult |
| 2205 Duplex | 35-80 | 45-100 | 14-35 | Very Difficult |
| 2507 Super Duplex | 25-60 | 35-80 | 10-28 | Extremely Difficult |
Frequently Asked Questions
Two main challenges: 1) Work hardening - austenitic grades (304, 316) harden dramatically when the tool rubs instead of cuts. 2) Poor thermal conductivity - heat concentrates at the cutting edge instead of dissipating into the chip. This combination causes rapid tool wear and requires specific cutting strategies.