The effect of organic modification on the surface of silicon nitride powders has been investigated. The Si3N4 powder modified by tartaric acid and PEI was characterized by using granulometer, X-ray diffraction, thermogravimetric analysis, diffuse reflectance infrared Fourier transform spectroscopy, SEM. The results show that modifier on Si3N4 powder surface is chemical adsorption coating. The addition of modifier dose not change phase, but modified particles have spherical tendency. Modifier coating occurred oxidative decomposition in 200-400°C. surface modification can improve the fluidity of powder and density of green bodies. As the amount of modifier increased, the angle of repose and compression degree firstly decreases and then increases. The angle of repose of artaric acid and PEI modified powder decrease 9 º and 12º, compression degree decline 15% and 20% respectively.
Surface Modification of Polymer Fine Powder
