Grinding is a key step on the manufacturing process of WC-Co cemented carbides (hardmetals). A systematic study of grinding effects on the surface integrity of hardmetals is conducted. It is done by combining diverse advanced characterization techniques: XRD, FESEM/EBSD, FIB – 3D tomography and TEM/PED. The study is conducted in a fine-grained WC-Co grade with three different surface finish conditions: ground, polished, and ground+termal-annealed.
It is found that grinding induces significant alterations in the surface integrity of hardmetals. Main changes included generation of a topographic texture, anisotropic distribution of microcracks at the subsurface, phase transformation of binder, and large compressive residual stresses. On the other hand, high temperature annealing resulted in: relief of residual stresses, but without inducing any change in terms of damage within the carbides; as well as reversión of phase transformation and emergence of an unexpected microporosity within the binder.