Mapping of mechanical properties of WC-Co using nanoindentation

High-resolution measurements of mechanical properties are of immense import ance in metallurgy. Measuring the intrinsic properties of each phase separa tely in multiphase materials gives information that is valuable for the dev elopment of new materials and for modelling. In this work, nanoindentation has been used to reveal mechanical properties of different phases in WC-Co with very high resolution. The resolution limits of the equipment and this material as well as various techniques to accomplish the measurements were evaluated. By making indents only 0.1 mu m apart and using very low loads ( 1 mN) it was possible to distinguish between the two different phases, WC a nd Co. Maps created from the measured properties, hardness and Young's modu lus, were in excellent agreement with SEM images of the same area. Furtherm ore, it was also possible to detect an increased hardness of the Co binder phase by a factor of four as compared to the bulk hardness of Co. This work verifies experimentally what several authors have proposed earlier based o n modelling.