Industry
Invar Machining for Metrology, Calibration and Test Equipment
We match your RFQ for a calibration artifact, reference standard or test fixture with up to three machine shops that cut Invar and Super Invar, so you get quotes to compare rather than one shop’s answer.
Why Metrology, Calibration & Test Equipment programs specify these alloys
Metrology and calibration equipment depends on a reference that does not move. A CMM calibration bar, a gauge block or a test fixture is only as good as its own dimensional stability across the small temperature swings every lab room has, and Invar 36 and Super Invar narrow that error by nearly an order of magnitude compared with steel at the same length.
This is a genuinely different buyer than most of the site serves. A calibration lab or metrology equipment maker usually needs one part or a handful, machined and stabilized to a tight flatness and finish, with clear documentation, not a production run. The sourcing problem is about getting a comparable quote and a shop that understands stress relief and reference temperature, not about unit price at volume.
Where Metrology, Calibration & Test Equipment uses Invar, Kovar and Alloy 42
CMM calibration artifacts
Step gauges, ball bars and length bars used to verify coordinate measuring machines against a known reference.
Reference standards and gauge blocks
Length and flatness standards where Invar’s low CTE reduces the temperature term in the measurement uncertainty budget.
Test and calibration fixtures
Mounting brackets, carriers and check fixtures that must hold their dimensions through repeated use in a test lab.
Interferometer and optical test hardware
Mounts and benches for laser interferometers and other optical metrology instruments that need a dimensionally stable base.
What to put on the RFQ, and what to vet in a supplier
We match your RFQ. You still own supplier qualification. These lines get you a comparable quote and a shop that can answer the qualification questions your program asks.
State the reference temperature for every tight tolerance, not just the number.
Specify flatness, parallelism and surface finish on measuring faces, not just linear dimensions.
Say whether Invar 36 or Super Invar is required, or ask the shop to recommend based on the operating environment.
Call out the stress relief or stabilization cycle, or ask the shop to propose one for the part’s intended service life.
Tell the shop where and how the part will be calibrated so its first article inspection lines up with the receiving lab.
Request the mill certificate and, if the design depends on it, measured CTE per ASTM E228 for the heat lot.
Metrology, Calibration & Test Equipment guides
- Process
Machining Invar CMM Calibration Bars and Reference Gauges
Machining Invar CMM step gauges, ball bars and length bars: the tolerances, finish and stabilization a reference artifact needs before a cal lab certifies it.
- Materials
Machining Invar Reference Standards and Gauge Blocks
Invar reference standards for metrology labs: why the low CTE cuts temperature-driven uncertainty versus steel gauge blocks, and the tolerances a lab specifies.
- Choosing a Supplier
Supplier Sourcing for Metrology Lab Invar Components
How a metrology lab sources machined Invar parts: low volume realities, what to put on the RFQ, and why the lab's own accreditation establishes traceability.
- Process
Reading an Invar CMM Inspection Report: What Each Number Means
How to read a CMM inspection report for a machined Invar part: measurement temperature, soak time, GD&T callouts and what to check before accepting parts.
- Process
Invar Machining Tolerances: What a Shop Can Hold and What It Costs
Typical Invar machining tolerances by feature, why 20 °C inspection matters, which GD&T callouts count on Invar and how to turn a temperature band into a CTE.
- Materials
Long-Term Dimensional Stability: Does Invar Age After Machining?
Whether machined Invar parts keep moving over months or years after stress relief, and what shops do to minimize long-term dimensional drift beyond the initial process.
- Choosing a Supplier
Invar Mill Certifications: What a Certified Material Report Should Show
What a standard Invar 36 or Kovar mill cert includes, when to ask for measured CTE data, and how to read a certified material test report before it reaches your shop.
Alloy pages: Invar 36 machining, Super Invar machining, Kovar machining, Alloy 42 machining. Spec numbers and CTE by temperature band on the Invar specs reference.
Have a drawing ready?
Send the short version now. We will ask for anything missing. For full details up front use the full RFQ form. Reply within 24 business hours.
Your files go only to the shops we match. Ask for an NDA and nothing is shared until it is signed.
Questions from Metrology, Calibration & Test Equipment buyers
Something else? Email .
Are your matched shops certified, or is a part from them NIST-traceable?
No. We are a matching service, not a calibration lab, and we never claim a shop or a part is NIST-traceable or ISO/IEC 17025 accredited. A machine shop machines, stress relieves and delivers the part with a mill certificate and an inspection report. Traceability to a national measurement standard is established afterward by your own accredited calibration lab or a third-party metrology lab that measures the finished part.
Why use Invar instead of steel for a calibration artifact?
Invar 36 expands about 1.2 to 1.6 ppm/°C near room temperature, roughly a tenth of tool steel’s typical 10 to 12 ppm/°C. Over a 500 mm artifact, that keeps the length error from an ordinary few degrees of room drift small relative to the tolerance, which steel cannot promise at the same length.
How many parts do you typically handle for a metrology lab RFQ?
Usually one to a handful. This is a low-volume, high-precision niche, and the shops we match understand that setup and first article inspection dominate the quote, not unit price at scale.
Can a shop supply a measured CTE for the material instead of a typical handbook value?
Yes, as a separate line item. A standard mill certificate confirms chemistry only. Measured CTE per ASTM E228 for the specific heat lot costs more and takes longer, so specify it on the RFQ if your design depends on the number.
Do you sell reference standards or calibration equipment?
No. We match your RFQ with machine shops that cut Invar and Super Invar to your drawing. We do not manufacture, distribute or calibrate parts ourselves.