Leeb vs. UCI: Which Portable Hardness Testing Method is Right for You?
What is the Leeb Method?
The Leeb method uses rebound velocity to determine hardness — ideal for large or heavy metal parts like castings and forgings.
What is the UCI Method?
Ultrasonic Contact Impedance (UCI) uses frequency shifts to assess hardness in thinner parts and heat-treated components. It’s popular in aerospace and precision manufacturing.
Key Differences Between Leeb and UCI
Learn how these methods compare in accuracy, surface prep requirements, and suitable materials — plus calibration needs.
Which One Should You Choose?
We help you select the best method based on your industry, material type, and mobility needs in the field.
Choosing between Leeb and UCI (Ultrasonic Contact Impedance) portable hardness testers can be tricky. Both offer reliable, non-destructive testing options—but each method shines in different use cases. In this guide, we break down the differences to help you pick the right solution for your materials, accuracy requirements, and work environment.
How the Leeb Method Works
The Leeb method (also called dynamic rebound testing) uses an impact device to strike the material. The rebound velocity is measured and converted into a hardness value. It’s fast, field-ready, and ideal for large, homogeneous materials.
Best For:
- Steel, cast iron, and forgings
- Large components and heavy parts
- Applications where surface prep is minimal
Advantages:
- Very portable and rugged
- Quick readings and wide range of materials
- Often less expensive
Limitations:
- Requires a relatively flat, smooth surface
- Less accurate on thin or small parts
- Not ideal for coatings or surface-hardened materials
How the UCI Method Works
UCI (Ultrasonic Contact Impedance) testers apply a Vickers-like diamond tip and measure the shift in ultrasonic frequency caused by material resistance. This allows for precise, low-force testing on thinner components or complex geometries.
Best For:
- Heat-treated and surface-hardened parts
- Thin-walled components
- Weld seams, blades, gears, and small areas
Advantages:
- High precision on small or narrow test zones
- Minimal surface damage
- Works well on complex shapes or coatings
Limitations:
- Typically more expensive
- Requires a skilled operator
- More sensitive to surface prep and calibration
Leeb vs. UCI: Comparison Table
| Feature | Leeb | UCI |
|---|---|---|
| Accuracy on thin parts | Low | High |
| Best for heavy components | Yes | No |
| Surface-hardened parts | Limited | Excellent |
| Portability | Very high | High |
| Ease of use | Beginner-friendly | Requires training |
Our Verdict: Choose Based on Application
If you’re testing large, machined parts in the field and need speed, go with Leeb. If you’re working with surface-treated parts, fine details, or complex geometries, UCI is the better choice—even if it takes more setup.
Need Help Choosing?
We research, compare, and review the best portable hardness testers available to Canadian buyers. Check out our expert picks and trusted affiliate recommendations in our product guide.
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