VT machining specialises in CNC Punching 440C Stainless Steel. Because 440C Stainless Steel is corrosion resistant, strong and hygienic, and its machinability is moderate; work-hardens, so positive-rake tooling and steady feeds are used to avoid glazing, we plan each job around the grade to protect accuracy and surface quality.
CNC Punching Capability for 440C Stainless Steel
- Austenitic/martensitic grades
- Corrosion resistant
- Tolerance to ±0.01 mm
- Typical hardness 70–200 HB (annealed)
440C Stainless Steel Material Data
| Density | 8.00 g/cm³ |
|---|---|
| Tensile strength | 515 MPa |
| Yield strength (0.2%) | 205 MPa |
| Hardness | 170 HB |
| Melting point | 1400–1450 °C |
| Thermal conductivity | 16.2 W/m·K |
| Thermal expansion | 17.3 ×10⁻⁶/K |
| Electrical conductivity | 2.4% |
| Machinability (C36000 = 100%) | 45% |
| Grades we run | 303, 304/304L, 316/316L, 321, 410, 416, 420, 17-4PH, 2205 duplex |
Published typical values for 304. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
It work-hardens the moment a tool dwells. Constant feed and positive-rake tooling; a rubbing pass leaves a glazed skin the next tool cannot get through.
Machining 440C Stainless Steel with CNC Punching
When punching 440C Stainless Steel, machinability is moderate; work-hardens, so positive-rake tooling and steady feeds are used to avoid glazing. Our process plan reflects this so the finished part holds its tolerances without distortion or poor finish.
Documented parameters for 440C Stainless Steel mean predictable cycle times and stable, repeatable results.
Achievable Tolerances for CNC Punching 440C Stainless Steel
| Feature | Standard | Precision |
|---|---|---|
| Hole position across sheet | ±0.15 mm | ±0.10 mm |
| Hole diameter | ±0.10 mm | ±0.05 mm |
| Overall blank size | ±0.20 mm | ±0.10 mm |
| Minimum hole | 1.0 × thickness | 0.8 × thickness |
| Hole-to-edge distance | 2.0 × thickness | 1.5 × thickness |
| Burr height | 0.08 mm | 0.03 mm (deburred) |
| Sheet thickness range | 0.5–6.0 mm | 0.5–3.0 mm |
Standard is what a normal quotation assumes. Precision is available on nominated features and is priced separately, because it needs extra setups, in-process gauging and CMM verification. Call out only the features that need it — blanket-tightening a drawing is the single most common reason a quote comes back expensive.
Secondary Operations & Finishing
Most 440C Stainless Steel parts need some finishing, which we manage in-house or through vetted partners. Options include deburring and edge-breaking, heat treatment, surface grinding, polishing, and plating or anodising for corrosion resistance and appearance. Give us the finished-part requirement and we will sequence every operation correctly.
CNC Punching Tolerances & Surface Finish
Punched 440C Stainless Steel holds hole-position repeatability around ±0.10 mm across the sheet, with consistent hole quality when punch/die clearance is matched to the gauge.
Exact achievable figures depend on the alloy, the feature size and the part geometry. Tell us which dimensions are critical and we will advise feasibility up front.
Why 440C Stainless Steel?
Customers select 440C Stainless Steel for CNC Punching because it is corrosion resistant, strong and hygienic. We handle grade verification and any required heat treatment or finishing.
Design Tips for CNC Punching 440C Stainless Steel
Small design adjustments often cut cost and lead time. Keeping hole-to-edge and hole-to-hole distances at least 1.5–2× thickness avoids distortion and tearing in punched 440C Stainless Steel. If you send your model early, we will return practical DFM feedback before you commit to production.
CNC Punching Quality & Inspection
Quality is built in, not inspected on. We monitor key features during the run and confirm them at final inspection, with CMM verification available for tight tolerances. We provide the inspection and traceability records your quality system requires.
Applications of CNC Punching 440C Stainless Steel
440C Stainless Steel parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
How to Order CNC Punching 440C Stainless Steel
Starting your project takes one email. Send your CAD or 2D drawing, the 440C Stainless Steel grade and condition, the quantity and any finish or inspection requirements. We respond quickly with price, lead time and any DFM notes, in clear English.
Finishing Options for 440C Stainless Steel
| Finish | Thickness / effect | Why it gets specified |
|---|---|---|
| Citric passivation | — | ASTM A967 / AMS 2700, removes free iron |
| Electropolish | 5–25 µm removed | Ra improves by roughly half, hygienic surface |
| Brushed / grained | Ra 0.4–1.6 µm | No. 4 finish, directional |
| PVD coating | 2–5 µm | TiN, TiCN for wear surfaces |
| Deburr / edge break | 0.05–0.3 mm | All parts unless the drawing says otherwise |
| Bead blast | Ra 1.6–3.2 µm | Uniform matt finish, hides tool marks |
| Laser marking | — | Part number, lot code, data matrix |
No drawing yet? Build one in the browser.
Set the metal, dimensions and features, watch the 3D model update as you type, then switch to the 2D sheet to add dimensions and tolerances. Download it or send it straight to us with your RFQ.
What We Need to Quote CNC Punching 440C Stainless Steel
- GeometrySTEP or IGES for the 3D model, plus a PDF drawing if you have tolerance callouts. A dimensioned sketch is enough to start.
- MaterialThe exact 440C Stainless Steel grade and condition — temper, heat-treat state or hardness. If you are not sure, tell us the function and we will suggest one.
- QuantityPrototype count and the expected annual volume. Both change how the part is made and therefore what it costs.
- TolerancesWhich features are critical. Everything else runs to our standard tolerance, which is what keeps the price sensible.
- FinishSurface treatment, cosmetic requirements, and any faces that must be masked.
- DocumentsWhether you need a material certificate, dimensional report, FAIR or PPAP with the shipment.
Missing something from the list is not a problem — send what you have. We will come back with the specific questions rather than a generic form.
440C Stainless Steel in Other Processes
Related
Send the drawing, the 440C Stainless Steel condition and the quantity — pricing and lead time come back the same or next business day.
Request a QuoteFrequently Asked Questions
What surface finish is achievable on 440C Stainless Steel with CNC Punching?
Surface finish on 440C Stainless Steel is controlled to your specification; we confirm the achievable Ra against your callout.
What is CNC Punching 440C Stainless Steel and how is it done?
CNC Punching 440C Stainless Steel refers to cNC turret punching shears holes and form features in sheet metal using programmable tooling for fast, repeatable patterns. Applied to 440C Stainless Steel — corrosion resistant, strong and hygienic — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.
How clean are the edges produced by CNC Punching on 440C Stainless Steel?
Punched 440C Stainless Steel edges are clean when punch/die clearance is correct; we set clearance to the gauge and can add deburring if specified.
What material thickness or size range suits CNC Punching 440C Stainless Steel?
Punching suits 440C Stainless Steel sheet roughly 0.5–6 mm thick, with clearance matched to the gauge.