Repeatable, Reproducible Preparation and Hardness Depth Measurement of Surface-Hardened Steels

摘要

Accuracy and repeatability are key when measuring the microhardness of surface-hardened steels. What are the problems, and what can be done to assure accuracy? Surface hardening of steel is performed to increase the strength and wear properties of the material. One of the prerequisites for hardening is sufficient carbon and alloy content. If there is sufficient carbon content, the steel can be directly hardened. Otherwise, the surface of the part has to be carbon or nitrogen enriched using diffusion-treatment hardening techniques. Hardened steel parts are typically used in moving or rotating applications where high wear resistance and/or strength is required, such as gear and engine parts, injection pumps and nozzles, etc. Since hardening makes the steel brittle, and it is desired to retain the ductility in the material core, it is required to control the hardness depth -thus the term surface hardening.