Eddy-Current Testing of the Wear Resistance of Laser-Hardened Carburized Chromonickel Steel and the Quality of Laser Hardening of Drill Bits

摘要

Features of eddy-current testing of carburized chromonickel steel 30XH3A subjected to processing with continuous laser radiation, subsequent treatment with cold at -196°C (reducing the content of retained austenite in the carburized layer from 25-40 to 5-10 vol %), and tempering in the temperature range 100-400°C are studied. It is shown that the eddy-current method can be used to detect the presence of a laser-hardened wear-resistant layer on the steel surface and evaluate an abrupt decrease in the abrasive wear resistance of steel hardened with laser radiation, additionally treated with cold, and then exposed to low-temperature tempering. The possibility of eddy-current testing of the quality of laser hardening of roller paths of the bearing unit of rock-drilling bits manufactured from carburized steel 20XH3A using an attachable transducer with a protruding rod core is established