Portable hardness tester based on the Ultrasonic Contact Impedance (UCI)method, using a Vickers diamond indentor. Hardness tester Portable hardness tester based on the Ultrasonic Contact Impedance (UCI)method, using a Vickers diamond indentor. The hardness value is electronically measured across the Vickers diamond indented surface and displayed instantly. Specially designed high-tech probes ...