Additive manufacturing of WC-20Co components by 3D gel-printing

3D gel-printing (3DGP) is a novel manufacturing technology, which builds a 3D component by depositing and gelating metal slurry layer by layer. In this paper, the hydroxyethyl methacrylate (HEMA) based slurries with WC-20Co solid loading of 47-56 vol% were directly formed by 3DGP and then sintered in a vacuum furnace. The WC-20Co slurries exhibited suitable fluidity and shear thinning behavior, which were beneficial for 3DGP forming process. The effects of 3DGP processing parameters, such as the internal diameter of print nozzle and filling rate, on the surface roughness and dimensional accuracy of as-printed green bodies were studied. The influence of solid loading on rheological property of WC-20Co slurry, green density, sintered density and mechanical properties of sintered samples were also investigated. The results show that the samples can be printed with good shape, appropriate precision and homogeneous microstructure. The sintered samples have good shape retention and uniform microstructure. The density, hardness and transverse rupture strength of the optimal sample were 13.55 g/cm3, HRA 87.7 and 2612.8 MPa, respectively. 3DGP has unique advantages in near-net forming for complex shape WC-20Co components.