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Stainless Steel CNC Machining Services
10 Common Machining Stainless Steel Problems
Poor Chip Control
High Cutting Force
Poor Surface Finish
High Cutting Temperature
Dimensional Inaccuracy
Chatter & Vibration
Low Machining Efficiency
Material Grade Sensitivity
Common Stainless Steel Grades for CNC Machining
| Grade | Category | Machinability | Corrosion Resistance | Typical Applications |
|---|---|---|---|---|
| 303 | Austenitic | ★★★★★ | ★★★☆☆ | Shafts, threaded parts, fittings, precision turned components |
| 304 / 304L | Austenitic | ★★★★☆ | ★★★★☆ | General machinery, food equipment, flanges, brackets, structural parts |
| 316 / 316L | Austenitic | ★★★☆☆ | ★★★★★ | Medical devices, marine equipment, chemical processing, valves |
| 410 | Martensitic | ★★★★☆ | ★★★☆☆ | Pump shafts, valves, industrial components |
| 416 | Martensitic | ★★★★★ | ★★☆☆☆ | High-speed CNC turning, gears, precision shafts |
| 420 | Martensitic | ★★★☆☆ | ★★★☆☆ | Wear-resistant parts, surgical instruments, molds |
| 430 | Ferritic | ★★★★☆ | ★★★☆☆ | Automotive trim, appliance components, decorative parts |
| 440B / 440C | Martensitic | ★★☆☆☆ | ★★★★☆ | Bearings, cutting tools, hydraulic components, precision wear parts |
| 17-4 PH (630) | Precipitation Hardening | ★★★☆☆ | ★★★★☆ | Aerospace, robotics, semiconductor equipment, high-strength structural parts |
| 2205 Duplex | Duplex | ★★☆☆☆ | ★★★★★ | Offshore equipment, oil & gas, chemical systems |
| X30N (30Cr15Mo1N) | High-Nitrogen Martensitic | ★★☆☆☆ | ★★★★☆ | Premium wear-resistant precision parts, high-performance mechanical assemblies |
Stainless Steel Heat Treatment Services
Heat treatment improves the mechanical properties and dimensional stability of stainless steel CNC machined components. Depending on the stainless steel grade and application requirements, different heat treatment processes can be applied to achieve higher strength, hardness, wear resistance and service reliability.
| Heat Treatment Process | Applicable Stainless Families | Core Temperature & Cooling | Hardness After Treatment | Main Function | Common Parts |
|---|---|---|---|---|---|
| Stress Relief Annealing | All grades（304/316/17-4PH/2205/440C） | 300–600℃, slow air cool |
Usually unchanged ≈150–220 HB (depending on grade) |
Release residual stress from CNC cutting, prevent thin-wall deformation & cracking; reduce work hardening | Thin housing, long shafts, welded brackets, robot structural parts |
| Solution Treatment | Austenitic (304/316L), Duplex (2205), 17-4PH pre-treatment | 1020–1150℃, rapid water quench |
Soft condition 304/316L: ≈150–200 HB 17-4PH: ≈300 HB |
Dissolve carbide, recover full corrosion resistance, soften material for machining; balance ferrite/austenite for duplex steel | Marine valve, chemical equipment, semiconductor cavity, offshore fittings |
| Bright Annealing | 304/316/430 decorative & medical parts | Controlled atmosphere furnace, H₂ shielding |
Similar to annealed condition ≈150–220 HB |
No oxidation scale, mirror base surface, skip pickling | Food machinery components, medical housings, decorative trim |
| Quench & Temper | Martensitic：410/416/420/440B/440C/X30N | Quench 980–1080℃ oil/water cool; temper 180–550℃ |
410: HRC 35–45 420: HRC 45–55 440C: HRC 58–60 |
Boost hardness, improve wear resistance, balance toughness and strength | Bearing, cutting inserts, pump shaft, surgical tool, precision wear parts |
| Precipitation Aging | 17-4 PH (630), 15-5PH | Solution first + aging 480–620℃ (H900/H1025/H1150) |
H900: HRC 40–47 H1025: HRC 32–38 H1150: HRC 28–35 |
Ultra-high tensile strength, maintain good corrosion resistance | Aerospace fasteners, robotic joint, high-strength semiconductor fixtures |
| Vacuum Heat Treatment | All precision grades (medical/aerospace) | Vacuum sealed furnace |
Depends on material & process Typically ±1–2 HRC consistency |
Zero surface oxidation, minimal deformation, consistent hardness | 5-axis precision parts , miniature medical implants, high-tolerance mold inserts |
