The Swiss-made Equotip 550 Portable Hardness Tester from Proceq is now even more impressive with introduction of the Ultrasonic Contact Impedance (UCI) probe. Along with the range of Leeb probes and Portable Rockwell probe, the Equotip 550 offers the ultimate NDT solution to your hardness testing requirements.
The UCI Measuring Principle
The UCI (Ultrasonic Contact Impedance) method uses the same pyramid-shaped diamond as a conventional Vickers hardness tester. Unlike Vickers testing, no optical evaluation of the indentation is required, enabling fast and portable measurements. The UCI method excites a rod into an ultrasonic oscillation. The test load is applied by a spring and typically ranges from 1 to 5 kg of force (HV1 – HV5). As the diamond is forced into the material, the frequency of the rod oscillation changes in response to the contact area between the diamond and the material under test. The instrument detects the shift in frequency, converts it to a hardness value which is immediately displayed on the screen. While measurements are shown in Vickers, automatic conversions to Rockwell and Brinell can be displayed. The UCI method excels in testing of small and complex shaped parts comprised of fine-grained metals, while the rebound method is preferred for larger, coarse-grained forgings and castings.
Advantages of UCI for NDT
- Measures only surface hardness
- Extremely fast with operator guidance when to apply and release
- Highly portable
- Test in any direction but must be perpendicular to the surface
- Can measure hardness of a coating, plating or case hardened surface
- Indentation is very small therefore non-destructive
- Small probe can access the HAZ of welds, gear teeth and splines for example
- Adjustable load for material hardness and coating with no need to change UCI probe
