The ultrasonic hardness tester is an advanced instrument based on ultrasonic vibration. An indenter applies a constant force to the test surface while transmitting ultrasonic signals; materials with different hardness exhibit different damping characteristics—harder materials attenuate the vibration faster, while softer materials attenuate it more slowly. The hardness value is calculated based on this attenuation. The instrument can measure workpieces of various shapes and sizes, from large components to small precision parts, and provides reliable results even on relatively rough surfaces. It is widely used in machining, mold manufacturing, aerospace, petrochemical, shipbuilding, automotive manufacturing, rail transportation, pressure vessels, and pipeline inspection.