Rheological property and solvent debinding behavior of microcrystalline wax based feedstocks for injection molding

Microcrystalline wax was mixed with the WC–10Co (YG10) powders to obtain the injection molding feedstocks as the main component of the binders. The non-Newtonian index, viscous flow activation energy, and synthetic rheological factor of the feedstocks were calculated by linear fitting, and the rheological properties of the feedstocks at the different temperatures and shear rates were investigated. The kinetic behavior of the solvent debinding for green bodies was investigated by analyzing the weight loss of the green bodies in the different debinding solvents at the different temperatures. The results show that, the microcrystalline wax based feedstocks exhibit the shear thinning characteristics of pseudoplastic fluid. The feedstocks have the stable sensitivity to the shear rate and temperature fluctuation, and show the good comprehensive rheological properties. The removal of soluble binder components mainly occurs in the pre-solvent debinding stage, which is controlled by diffusion, and the diffusion coefficient increases with the decrease of the thickness and volume of the green body and the increase of the debinding temperature.