Process & Material
Kovar Micro EDM Feasibility Review
Kovar can be machined with Micro EDM when the geometry matches micro holes, micro slots, miniature cavities, fine pins, and sub-millimeter precision details. Kovar is a controlled-expansion iron-nickel-cobalt alloy used where metal-to-glass or ceramic expansion matching matters; the supplied condition affects support, discharge energy, finishing, and inspection.
Quick Answer
Micro EDM is suitable for Kovar when the feature is a micro hole, micro slot, miniature cavity, fine pin, or other sub-millimeter detail. The supplied condition must be stated before tolerance and surface requirements are confirmed.
Key Material Decisions
How This Material Behaves
A controlled-expansion iron-nickel-cobalt alloy used where metal-to-glass or ceramic expansion matching matters. In Micro EDM, the supplied condition directly changes discharge stability, electrode wear, edge quality, and the finishing plan—especially at micro scale.
Choosing the Right Condition
Choose Micro EDM for micro holes, micro slots, miniature cavities, fine pins, and sub-millimeter precision details. State the exact Kovar condition, then set tolerance, finish, support, and inspection from the controlled feature rather than the whole part.
Risks to Manage
When Micro EDM is used on a sub-millimeter slot, hole, or datum feature in Kovar, two effects occur together: thermal history, sealing faces and contamination control are more important than generic alloy-steel wording, while micron-level electrode wear and debris change the gap while the small section relaxes or rounds at the edge. The combined result is that the feature can drift in size and pitch while also losing the edge geometry that makes it functional. Control it by stage or replace the electrode, use low-energy finishing, control micro-flushing and temperature, and verify the feature with metrology that resolves the remaining tolerance.
How Micro EDM Works on Kovar
Micro EDM uses very small electrodes and low-energy discharges to create miniature conductive features without cutting force. On Kovar, the supplied condition changes dimensional stability, discharge response, and surface behavior.
Micro EDM Capability Reference
| What you're asking | What you can expect |
|---|---|
| Feature types | micro holes, micro slots, miniature cavities, fine pins, and sub-millimeter precision details |
| Tolerance | ±0.002–0.010 mm |
| Surface finish | Ra 0.1–1.6 μm |
| Feature scale | Sub-millimeter holes, slots, and cavities |
| Primary micro limit | Electrode wear and measurement resolution |
| Main limitation | Loose-tolerance or easily accessible features are rarely economical with Micro EDM. |
Material Condition Reference
| Condition | What to expect | Watch out for | Surface notes |
|---|---|---|---|
| solution annealed | Use stable support and conservative energy. | High-temperature alloys can retain a hard recast layer. | Identify fatigue and hot-section faces before finishing. |
| cold-worked or stabilized | Account for cold-work and service stress. | Thin features can move and electrode wear can grow corners. | Use low-energy finishing and selective metallurgical inspection. |
How This Material Behaves
Kovar does not behave the same in Micro EDM across every supplied condition. In EDM, this means sealing edges can be dimensionally correct yet unusable if recast, contamination, or residual stress disrupts the later joining process. Use clean finishing passes, protect seal surfaces from handling damage, and define post-EDM cleaning and inspection before brazing or sealing. At micro scale, material edge behavior and residual stress are the same order as electrode wear, spark gap, flushing, and measurement uncertainty. The process plan must reserve tolerance for all of them.
Surface Integrity and Post-Process
For Kovar in Micro EDM, use lower-energy finishing and inspect critical surfaces when fatigue, sealing or corrosion performance is specified. Assign fine finish, recast, edge, and post-process requirements only to the functional Micro EDM faces that need them.
Kovar Micro EDM Checkpoints
- Confirm that the feature matches micro holes, micro slots, miniature cavities, fine pins, and sub-millimeter precision details.
- State the supplied condition: solution annealed and cold-worked or stabilized.
- Mark the controlled dimensions, functional surfaces, datum scheme, and inspection method.
Typical Parts and Features
- turbine and energy features
- corrosion-resistant inserts
- precision seals
- micro holes
- micro slots
- miniature cavities
Limits and Better Alternatives
Main Limit
Loose-tolerance or easily accessible features are rarely economical with Micro EDM. On Kovar, thermal history, sealing faces and contamination control are more important than generic alloy-steel wording; the supplied condition still controls support, finishing, and surface-integrity review.
Consider Another Route When
Use conventional EDM for larger features, precision laser processing for suitable thin geometry, or mechanical micro-drilling where a tool can reach.
Practical Next Step
Send the Kovar drawing with condition, controlled geometry, tolerance, functional surface callouts, quantity, and inspection requirements. If the route is unclear, we will compare Micro EDM with the adjacent EDM or conventional process.
Practical Takeaway
Kovar is compatible with Micro EDM when the feature matches the process access. The supplied condition determines support, finishing, surface control, and inspection.
Additional Project Information
Include application, destination and end-use notes together with the material, quantity and drawing requirements.
Project Details for Technical Review
Include application and end-use notes when they affect material, inspection, documentation, or export review.
- Process: Micro EDM
- Material: Kovar
- Drawing or part sketch
- Material grade
- Thickness / part size
- Quantity
- Tolerance and critical dimensions
- Surface finish or inspection requirement
STEP/STP, DXF, DWG, PDF, IGS/IGES or ZIP.
Confidential drawing review. NDA support available on request.
Frequently Asked Questions
Can Kovar be machined with Micro EDM?
Yes, when the feature is a micro hole, micro slot, miniature cavity, fine pin, or other sub-millimeter detail. Kovar is electrically conductive and the final route follows the feature geometry and supplied condition.
What controls Micro EDM on Kovar?
The main process controls are electrode wear, feature-to-electrode ratio, micro-flushing, aspect ratio, edge radius, thermal stability, and measurement resolution. The Kovar condition adds dimensional-stability and surface-integrity requirements.
What is the main risk?
When Micro EDM is used on a sub-millimeter slot, hole, or datum feature in Kovar, two effects occur together: thermal history, sealing faces and contamination control are more important than generic alloy-steel wording, while micron-level electrode wear and debris change the gap while the small section relaxes or rounds at the edge. The combined result is that the feature can drift in size and pitch while also losing the edge geometry that makes it functional. Control it by stage or replace the electrode, use low-energy finishing, control micro-flushing and temperature, and verify the feature with metrology that resolves the remaining tolerance.
What should I send for review?
Send the drawing, exact Kovar condition, controlled geometry, tolerance, functional surface requirements, quantity, and inspection expectations. If any item is undecided, send what you have and we will help complete the review.