Systematic study at the micro- and submicrometric length scale up to 600 ºC of 3D-inkjet printhead
RIU PERDRIX G. 1, ROA ROVIRA J. 1
1 Steros GPA Innovative, Barcelona, Spain
Unlike other engineered ceramic/metal products, hardmetals (also known as cemented carbides – WC-Co) displays interesting mechanical and physical properties, which makes it an ideal candidate for a wide range of uses in different fields and in particular for cutting tools applications. However, the manufacturing of WC-Co components has still a major drawback in production of highly complex three-dimensional (3D) shapes, microfeatures or structures with tailored porosity. The present work is focused on dry-electropolished WC-Co. A systematic nanomechanical study of a 3D-printed WC-Co grade is investigated. In doing so, nanoindentation technique is implemented, while the main deformation or damage mechanisms induced at the submicrometric length scale are investigated at different temperatures, from room up to 600 ºC. In general, three different approaches are followed to accomplish this research: (1) assessment of intrinsic hardness values as a function of crystallographic orientation from a room temperature up to 600 ºC and (2) the determination of effective hardness and flow stress through the Tabor’s equation of the metal cobalt binder. Finally, the elastic strain to break has been also determined for the main crystallographic orientations for the WC particles as a function of the temperature. The preliminary results highlight that the strength reduction with increasing temperature is attributed to metallic binder softening. On the other hand, the WC particles present an isotropic behavior when the testing temperature is over 500 ºC because, inside these particles, the dislocations and the stacking faults are the main deformation mechanisms induced at intermediate/high testing temperature.