CNC Reaming Alloy 42 is part of VT machining's grade-specific capability. Alloy 42 is matched/low thermal expansion for sealing, and we combine controlled machining with material-aware setup to produce parts that meet your specification.
CNC Reaming Capability for Alloy 42
- Matched/low thermal expansion
- Glass-to-metal sealing
- Tolerance to ±0.01 mm
- Electronics-grade
Alloy 42 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.
Machining Alloy 42 with CNC Reaming
Alloy 42 behaves predictably under CNC Reaming once parameters are dialled in: machinability is moderate; gummy, requires sharp tooling and careful thermal control, and we tune the operation accordingly.
We hold reference parameters for this grade, so repeat orders of Alloy 42 run consistently from one batch to the next.
Achievable Tolerances for CNC Reaming Alloy 42
| Feature | Standard | Precision |
|---|---|---|
| Linear dimension (< 100 mm) | ±0.05 mm | ±0.010 mm |
| Linear dimension (100–300 mm) | ±0.10 mm | ±0.025 mm |
| Hole diameter (reamed) | H9 | H7 |
| True position of hole pattern | ±0.10 mm | ±0.025 mm |
| Flatness over 100 mm | 0.05 mm | 0.015 mm |
| Perpendicularity | 0.10 mm | 0.020 mm |
| Surface finish, as machined | 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.
Secondary Operations & Finishing
Finished Alloy 42 parts can move straight into secondary operations under one roof. Typical add-ons are deburring, passivation, anodising, plating, blasting, polishing and laser marking. We coordinate the whole chain so you receive complete, inspection-ready parts.
Design Tips for CNC Reaming Alloy 42
We are happy to suggest design tweaks that improve manufacturability. Generous internal radii, sensible pocket depth-to-width ratios and avoiding very thin unsupported walls all reduce cost and improve accuracy in Alloy 42. If you send your model early, we will return practical DFM feedback before you commit to production.
Why Alloy 42?
Alloy 42 is chosen when a part needs what this grade offers — it is matched/low thermal expansion for sealing. We confirm the grade and any temper or heat-treat condition with you before machining.
CNC Reaming Quality & Inspection
We control quality throughout the process, not just at the end. In-process checks plus final inspection — including CMM where specified — keep every Alloy 42 part to print. Inspection reports, material certificates and first-article documentation can be supplied on request.
CNC Reaming Tolerances & Surface Finish
For CNC Reaming, 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 Reaming Alloy 42
Customers order CNC Reaming Alloy 42 components for everything from instrumentation to structural and functional assemblies. Whether you need a single prototype or recurring production volume, the same process discipline applies.
How to Order CNC Reaming Alloy 42
Getting a quote is simple. Share your model, the material grade, your quantity and target tolerances. You receive a clear quotation with lead time and honest manufacturability feedback.
Finishing Options for Alloy 42
| 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 Reaming Alloy 42
- 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 Alloy 42 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.
Alloy 42 in Other Processes
Related
Send the drawing, the Alloy 42 condition and the quantity — pricing and lead time come back the same or next business day.
Request a QuoteFrequently Asked Questions
What tolerances can you hold for CNC Reaming Alloy 42?
Achievable tolerances for Alloy 42 machining depend on the alloy, geometry and feature size. Milling holds positional and dimensional tolerances to around ±0.01 mm, tighter with precision setups. Exact figures are confirmed against your drawing callouts.
Which industries use CNC Reaming Alloy 42 parts?
CNC Reaming Alloy 42 parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Alloy 42 components are required.
Why is Alloy 42 a good choice for CNC Reaming?
Alloy 42 is matched/low thermal expansion for sealing, which makes it well suited to CNC Reaming. We tune the process to the alloy so the finished Alloy 42 machining part meets your dimensional and functional requirements.
What is CNC Reaming Alloy 42 and how is it done?
CNC Reaming Alloy 42 refers to reaming finishes drilled holes to a precise diameter and smooth surface in a single controlled pass. Applied to Alloy 42 — matched/low thermal expansion for sealing — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.
Does CNC Reaming Alloy 42 require dedicated tooling?
Most Alloy 42 machining work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.