Sauter-HMM-Leeb-Hardness-Meter-Sauter-HMM-P-When-a-hardness-test-is-carried-out-by-the-Sauter-HMM-Leeb-hardness-meter-an-impact-body-with-a-tungsten-carbide-test-tip-is-propelled-by-spring-force-against-the-surface-to-be-tested-from-which-it-rebounds-P-P-Impact-and-rebound-velocities-are-measured-by-the-following-method-a-permanent-magnet-integrated-into-the-impact-body-passes-through-a-coil-and-induces-an-electric-voltage-during-its-travels-back-and-forth-The-voltages-are-proportiona