Experimental study of asymmetrical tilt boundaries in WC-Co alloys

Maxime Pellan (1) , Sabine Lay (1) , Jean-Michel Missiaen (2)

1 SIMaP - Science et Ingénierie des Matériaux et Procédés
2 SPIN-ENSMSE - Centre Sciences des Processus Industriels et Naturels

The rotation angle distribution of grain boundaries with [2 -1 -1 0] misorientation axis in WC-Co alloys was investigated by electron backscatter diffraction for a range of cobalt contents. The effect of carbon content and sintering time was also studied. Preferred misorientations correspond to low-index boundary habit planes involving the basal or prismatic plane for at least one grain. The 26.2° [2 -1 -1 0] boundary was imaged by high resolution transmission electron microscopy. The joining of the mismatched planes at the boundary is accommodated by dislocations which are interpreted with reference to the 29.4° [2 -1 -1 0] boundary. The dislocation spacing and direction found experimentally are in agreement with calculated values obtained by the 02-lattice approach taking into account the misorientation and parametric misfit. The periodicity and characteristics of the dislocations indicate an optimization of the grain boundary structure and energy.

Domaines: Matériaux

Maxime Pellan, Sabine Lay, Jean-Michel Missiaen. Experimental study of asymmetrical tilt boundaries in WC-Co alloys. Acta Materialia, 2019, 167, pp.197-209. ⟨10.1016/j.actamat.2019.01.019⟩. ⟨hal-02014016⟩