CNC Precision Machining Invar

CNC Precision Machining Invar from VT machining delivers precision Invar parts produced to your exact drawing. Precision machining combines processes and inspection to hold the tightest dimensional and geometric tolerances, and we tune every parameter to the behaviour of Invar, which is ultra-low thermal expansion.

CNC Precision Machining Invar at VT machining
CNC Precision Machining Invar — produced in-house at VT machining

CNC Precision Machining Capability for Invar

  • Tolerance to ±0.002 mm
  • CMM-verified
  • Geometric/GD&T control
  • Temperature-controlled shop

Invar Material Data

Invar — typical properties, quoted for Invar 36 (FeNi36)
Density8.11 g/cm³
Tensile strength450–590 MPa
Yield strength (0.2%)275 MPa
Hardness130–160 HB
Melting point1427 °C
Thermal conductivity10.5 W/m·K
Thermal expansion1.2 (0–100 °C) ×10⁻⁶/K
Electrical conductivity2%
Machinability (C36000 = 100%)25%
Grades we runInvar 36, Super Invar 32-5, Alloy 42, Alloy 46

Published typical values for Invar 36 (FeNi36). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining Invar — what actually causes trouble

The low expansion is the whole point, so machining stress is the enemy. Rough, stress-relieve at 315–425 °C, then finish — otherwise the part moves after it leaves the machine.

How CNC Precision Machining Invar Works

Rotating multi-flute cutters remove material as the Invar workpiece is driven through programmed tool paths on 3-, 4- or 5-axis machining centres. Climb milling, step-over and depth-of-cut are set so chip load stays in the ideal band for the alloy.

Every job begins from your CAD model or 2D drawing. Fixturing and tool paths are planned so the most critical dimensions are produced in the most rigid, repeatable setup. Critical dimensions are checked on the first part and monitored through the run.

Achievable Tolerances for CNC Precision Machining Invar

CNC Precision Machining Invar — achievable tolerances
FeatureStandardPrecision
Linear dimension (< 100 mm)±0.05 mm±0.010 mm
Linear dimension (100–300 mm)±0.10 mm±0.025 mm
Hole diameter (reamed)H9H7
True position of hole pattern±0.10 mm±0.025 mm
Flatness over 100 mm0.05 mm0.015 mm
Perpendicularity0.10 mm0.020 mm
Surface finish, as machinedRa 1.6 µmRa 0.4 µm

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.

CNC Precision Machining Quality & Inspection

Consistent quality comes from disciplined process control. Critical dimensions on Invar parts are checked in-process and verified at final inspection using calibrated instruments and, where required, CMM measurement. Full documentation — dimensional reports, mill certs, FAIR — is available when your programme needs it.

Design Tips for CNC Precision Machining Invar

A few design choices make a real difference to cost and quality. Generous internal radii, sensible pocket depth-to-width ratios and avoiding very thin unsupported walls all reduce cost and improve accuracy in Invar. If you send your model early, we will return practical DFM feedback before you commit to production.

Working with Invar

Invar offers a useful combination of properties: it is ultra-low thermal expansion. Those characteristics shape how we approach milling — from tool and parameter selection to work-holding and coolant.

If your application is sensitive to alloy condition, we agree the specification in writing and document it. Stock is sourced from reputable suppliers so what you order is what you receive.

Secondary Operations & Finishing

We complete Invar components with the secondary steps your drawing calls for. We arrange heat treatment, surface treatment, marking and assembly as needed. Tell us the final spec and we will plan the full route so parts arrive ready to use.

CNC Precision Machining Tolerances & Surface Finish

For CNC Precision Machining, dimensional and positional tolerances around ±0.01 mm are routine, tightening toward ±0.005 mm on precision setups. Surface finish on machined faces typically falls in the Ra 0.4–1.6 µm range depending on tooling and pass strategy.

Final tolerances are governed by the material's behaviour, wall thickness and overall stiffness. We give honest DFM feedback if a callout would be costly or better achieved another way.

Applications of CNC Precision Machining Invar

CNC Precision Machining of Invar supports parts across aerospace, medical, automotive, electronics, semiconductor, energy and general industrial sectors. We scale from one-off prototypes to ongoing production while holding the same quality.

How to Order CNC Precision Machining Invar

Ordering Invar parts is straightforward. Provide the drawing, material, quantity and any certification needs. Our engineers reply — in English — with feasibility, pricing and a realistic lead time, usually within one business day.

Parts We Have Run in Invar

Three representative CNC Precision Machining Invar jobs, with the callouts that actually drove the process plan. Yours will differ — these are here so you can judge whether your part is in our range before you spend time on an RFQ.

Optical mount plate

Material
Invar
Size
160 × 160 × 12 mm
Key callouts
Hole pattern true position ±0.02 mm, flatness 0.01 mm
Batch
40 pcs

Roughed, stress-relieved overnight, then finished — the plate is too thin to hold flatness in one hit.

Vacuum chamber flange

Material
Invar
Size
Ø180 × 20 mm
Key callouts
Knife-edge seal Ra 0.4 µm, bolt circle ±0.05 mm
Batch
60 pcs

Sealing face finished last, then handled in gloves and bagged straight off the machine.

Robot end-effector bracket

Material
Invar
Size
180 × 90 × 30 mm
Key callouts
Bore pair concentric within 0.02 mm, weight reduction pockets
Batch
120 pcs

Pockets ganged so wall thickness never drops below 2 mm at the load path.

Finishing Options for Invar

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Deburr / edge break0.05–0.3 mmAll parts unless the drawing says otherwise
Bead blastRa 1.6–3.2 µmUniform matt finish, hides tool marks
Laser markingPart number, lot code, data matrix
Free — no sign-up

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.

Open the 3D + 2D Builder

What We Need to Quote CNC Precision Machining Invar

  • 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 Invar 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.

Other Metals for CNC Precision Machining

Other Processes for Invar

Send the drawing, the Invar grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.

Request a Quote

Frequently Asked Questions

What is CNC Precision Machining Invar and how is it done?

CNC Precision Machining Invar refers to precision machining combines processes and inspection to hold the tightest dimensional and geometric tolerances. Applied to Invar — ultra-low thermal expansion — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.

Why is Invar a good choice for CNC Precision Machining?

Invar is ultra-low thermal expansion, which makes it well suited to CNC Precision Machining. We tune the process to the alloy so the finished Invar machining part meets your dimensional and functional requirements.

What material thickness or size range suits CNC Precision Machining Invar?

We machine Invar across a broad size range; share your part envelope for confirmation.

Can VT machining make custom Invar parts to my drawing?

Yes. Invar Invar machining is made to order from your CAD/2D drawing. Share your geometry, material grade, tolerance and quantity and we will confirm feasibility, lead time and pricing.

Which industries use CNC Precision Machining Invar parts?

CNC Precision Machining Invar parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Invar components are required.

Does CNC Precision Machining Invar require dedicated tooling?

Most Invar machining work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.