Low Expansion NI · Ni-Co-Fe Alloy
Nickel Alloy Kovar
Nickel Alloy Kovar is a low expansion ni nickel alloy — glass-sealing low-expansion alloy. Typical values: 345 MPa yield, 8.36 g/cm³, rated to 200 °C. Available for CNC machining, Sheet metal at FabDigit.
Properties
Typical room-temperature values in the O (annealed) condition. Metric first, imperial in gray. The bars show where Kovar sits against the other 11 nickel alloy grades in the catalog.
Datasheet
| Yield strength | 345 MPa50 ksi |
|---|---|
| Tensile strength | 540 MPa78 ksi |
| Hardness | 160 HB |
| Density | 8.36 g/cm³0.302 lb/in³ |
| Specific strength (yield ÷ density) | 41 |
| Min service temp | -250 °C-418 °F |
| Max service temp | 200 °C392 °F |
| Electrical conductivity | 2.2 % IACS1.3 MS/m |
| Machinability | Fair40 / 100 |
| Weldability | Good60 / 100 |
| Formability | Very good75 / 100 |
| ISO 513 machining group | S |
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Against other nickel alloy grades
Strength versus weight in the nickel alloy family
Yield strength against density for every nickel alloy grade FabDigit runs. Kovar is highlighted; hover a dot for its name, or open the interactive family chart.
Manufacturability
The process limits FabDigit's quote engine applies to Kovar. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Fair40 / 100 |
|---|---|
| ISO material group | S.1 |
| Cutting speed (rough / finish) | 40 / 55 m/min |
| Minimum wall | 1.5 mm |
| Minimum internal radius | 2 mm |
| Drill depth limit | 3× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Better75 / 100 |
|---|---|
| Weldability | Good60 / 100 |
| Bendable | Yes |
Conditions and tempers
How Kovar is supplied and what each state is for. The default is what FabDigit quotes unless your drawing says otherwise.
| Condition | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
ODefault Annealed (O) | Softest — parts you will bend or deep-form; not for carrying load | — | — | — | — |
Heat treatment and post-processing
Operations FabDigit's suppliers routinely run on Kovar, ranked by how often they make sense for this grade.
Heat treatment
| Age (Inconel 718 standard) | Inconel 718 AMS 5662 cycle |
|---|---|
| Solution Anneal | Dissolve carbides; reset austenite (stainless) |
| Hot Isostatic Press (HIP) | Eliminate porosity in cast / 3DP parts |
Post-processing
| Manual Deburr | Deburrstandard |
|---|---|
| Edge Break (0.5mm) | Deburr |
| Shot Peen | Blast |
| Electropolish | Polish |
| CMM Inspection | Inspection |
| FAI Report | Inspection |
| Individual Bag | Packaging |
Surface finishes for Kovar
Coatings and treatments compatible with nickel alloy on the processes Kovar runs on. Pick them in the quote configurator or call them out on the drawing.
Passivation
- Electropolishing
Plating
- Gold Plating
- Silver Plating
Marking / Decoration
- Chemical Etching
- Dot Peen Marking
- Electro-chemical Etching
- Embossing / Debossing
- Ink Stamping
- Laser Marking
- Mechanical Engraving
- Steel Stamping
- Vibro Engraving / Scribing
Thermal Spray
- HVOF Coating
- Plasma Spray
Equivalent designations
Standards and trade names that resolve to Nickel Alloy Kovar in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- K94610
- ASTM
- F15
- Also called
- Alloy K
Stock forms
Raw-material forms FabDigit sources Kovar in.
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.