Non-aqueous gelcasting of AlN ceramics using a low-toxicity monomer (DMAA) as gelling agent

In this study, high-performance aluminum nitride (AlN) samples were prepared by gelcasting based on a low-toxicity monomer and organic solvents . We prepared a 50   vol% solid content AlN suspension with a solvent ratio of 3:1, 6   wt% N,N-dimethylacrylamide (DMAA) and 0.15   wt% Polyethyleneimine (PEI); after degassing, low viscosity and high stability were observed. It was proven that the AlN green bodies exhibited a bending strength of 18.68   MPa, which met the requirements for machining. An optimum debinding process was developed and the TG-DSC curves showed that the AlN green bodies were heated at 1   °C/min from 450 to 800   °C. The relative density, apparent porosity , bending strength, and thermal conductivity of the AlN sintered bodies prepared by non-aqueous gelcasting were 98.5%, 0.22%, 310   MPa, and 159   W   m −1   K −1 respectively, representing optimum conditions. The uniform miscrostructure of the sintered bodies was observed by SEM images.