WC-Co Hard alloys as dispersion-strengthened materials

Abstract

1. In Part I, it was demonstrated that the variations of the yield strength and hardness of WC-Co alloys with composition and carbide grain size are in accord with the Orowan and Ansell-Lenel theories of the dispersion strengthening of alloys. 2. In the present article, it is shown that the stress-strain curves for WC-Co alloys at small plastic strains are similar in shape and character to the stress-strain curves for dispersion-strengthened alloys with noncoherent and undeformable particles of a hard phase. The variation of the strengthening of WC-Co alloys with composition is entirely in agreement with the theory of the dispersion strengthening of alloys formulated by Fischer and co-workers. 3. Considering all the data analyzed in this work, it is possible to conclude that WC-Co hard alloys belong to the class of dispersion-strengthened materials in spite of the fact that they contain an unusually high proportion of strengthening phase and that, as revealed by metallographic examination, the grains of this phase are in contact.