VT machining provides CNC Lathe Machining Kovar for customers who need accurate, repeatable Kovar components. Because Kovar is matched thermal expansion for glass/ceramic seals, we adapt the process to suit — controlling the variables that matter for this alloy.

CNC Lathe Machining Capability for Kovar
- Live-tool capability
- Sub-spindle pickup
- OD/ID + cross features
- Diameter tolerance ±0.005 mm
Kovar Material Data
| Density | 8.36 g/cm³ |
|---|---|
| Tensile strength | 517 MPa |
| Yield strength (0.2%) | 340 MPa |
| Hardness | 140–160 HV |
| Melting point | 1450 °C |
| Thermal conductivity | 17.3 W/m·K |
| Thermal expansion | 5.1 (30–200 °C) ×10⁻⁶/K |
| Electrical conductivity | 3.5% |
| Machinability (C36000 = 100%) | 35% |
| Grades we run | Kovar / ASTM F15, Alloy 42, Alloy 52 |
Published typical values for Kovar (ASTM F15). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
Sealing surfaces must stay clean. Parts destined for glass-to-metal seals are degreased and handled without bare hands after final machining.
How CNC Lathe Machining Kovar Works
The Kovar bar or billet rotates in the spindle while single-point tools shape outer diameters, bores, faces, grooves and threads. Constant surface speed control keeps cutting conditions stable from large to small diameters.
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 Lathe Machining Kovar
| Feature | Standard | Precision |
|---|---|---|
| Outside diameter | ±0.05 mm | ±0.005 mm |
| Bore diameter | H9 | H6 |
| Length / shoulder position | ±0.10 mm | ±0.020 mm |
| Concentricity OD to ID | 0.05 mm TIR | 0.010 mm TIR |
| Roundness | 0.02 mm | 0.005 mm |
| Thread class | 6g / 2A | 4h / 3A |
| Surface finish, as turned | Ra 1.6 µm | Ra 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 Lathe Machining Tolerances & Surface Finish
Turned Kovar holds diameter tolerances to about ±0.005 mm with concentricity within 0.01 mm and good roundness. Turned finishes of Ra 0.4–0.8 µm are achievable with finishing passes and sharp tooling.
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.
Working with Kovar
Kovar offers a useful combination of properties: it is matched thermal expansion for glass/ceramic seals. Those characteristics shape how we approach turning — 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 Kovar 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 Lathe Machining Quality & Inspection
Consistent quality comes from disciplined process control. Critical dimensions on Kovar 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 Lathe Machining Kovar
A few design choices make a real difference to cost and quality. Consistent diameters, standard thread forms and avoiding extremely long, slender features help Kovar turned parts stay concentric and economical. If you send your model early, we will return practical DFM feedback before you commit to production.
Applications of CNC Lathe Machining Kovar
CNC Lathe Machining of Kovar 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 Lathe Machining Kovar
Ordering Kovar 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 Kovar
Three representative CNC Lathe Machining Kovar 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.
Nozzle body
- Material
- Kovar
- Size
- Ø12 × 46 mm
- Key callouts
- Ø0.6 mm orifice ±0.01 mm, internal taper 20°
- Batch
- 600 pcs
Orifice EDM-drilled after turning; a drill wanders at that diameter.
Bearing spacer
- Material
- Kovar
- Size
- Ø35 / Ø22 × 9 mm
- Key callouts
- Thickness ±0.005 mm, parallelism 0.005 mm
- Batch
- 4,000 pcs
Turned then double-disc ground — thickness this tight is not a lathe job.
Precision shaft
- Material
- Kovar
- Size
- Ø16 × 240 mm
- Key callouts
- OD h6, concentricity 0.01 mm TIR, keyway 5 H9
- Batch
- 1,000 pcs / year
Turned between centres so both journals share one datum.
Finishing Options for Kovar
| Finish | Thickness / effect | Why it gets specified |
|---|---|---|
| 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 Lathe Machining Kovar
- 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 Kovar 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 Lathe Machining
Other Processes for Kovar
Send the drawing, the Kovar grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
How clean are the edges produced by CNC Lathe Machining on Kovar?
Machined Kovar edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.
Can VT machining make custom Kovar parts to my drawing?
Yes. Kovar Kovar turning 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.
Why is Kovar a good choice for CNC Lathe Machining?
Kovar is matched thermal expansion for glass/ceramic seals, which makes it well suited to CNC Lathe Machining. We tune the process to the alloy so the finished Kovar turning part meets your dimensional and functional requirements.
What material thickness or size range suits CNC Lathe Machining Kovar?
Turned Kovar parts are produced from bar or chuck stock across a wide diameter range.
What surface finish is achievable on Kovar with CNC Lathe Machining?
Surface finish on Kovar is controlled to your specification; we confirm the achievable Ra against your callout.
What is the typical lead time and minimum order for CNC Lathe Machining Kovar?
CNC Lathe Machining prototypes for Kovar can be produced quickly and scaled to series production. Send your drawing and quantity and we will advise lead time and any minimum order.
