Research On 3D Printed SiC Ceramics Based On Organic Precursors

Organic precursor polymer-derived ceramics(PDC)technology is an emerging method for the production of ceramic materials,PDC have a more regular internal structure,fewer surface defects,and relatively low processing temperatures compared to ceramics prepared by traditional methods.3D printing technology provides a good option for manufacturing complex structures or porous ceramic materials.In this paper,Digital Light Processing(DLP)technology and organic precursor transformation method were used to explore a simple synthesis process for the preparation of silicon carbide ceramics.By adding glucose to the precursor solution,the porosity of the ceramic material can be greatly improved.In order to reduce the sintering temperature of silicon carbide ceramics,iron-containing compounds such as ferrocene were added as sintering additives to explore the reduction of their sintering temperature.The combination of PDC and 3D printing technology provides a simple,environmentally friendly and economical synthesis method for the synthesis of ceramic parts with complex structures.The specific research content is as follows:1.γ-(methacryloyloxy)propyltrimethoxysilane(KH-570)was hydrolyzed and polymerized in acidic condition.By reacting at room temperature for 3 h and 90°C for2 h,a precursor solution without sintering additives and low viscosity can be prepared,and then a complex shape of "ceramic green body" is obtained by DLP printing for further light curing treatment.The ceramic green body was sintered at a high temperature of 1600°C under a nitrogen atmosphere to obtain a ceramic sample,and according to the characterization results,silicon carbide had been formed in the ceramic sample.2.Using glucose as a carbon source,adding it to the precursor solution prepared from γ-(methacryloyloxy)propyltrimethoxysilane(KH-570),using DLP to print a ceramic green body with a complex shape,which is cured by ultraviolet light and sintered at a high temperature of 1600°C.The results show that the proportion of silicon carbide in the ceramic sample is greatly improved.The optimal amount of glucose added is 1 wt%,and the porosity of the prepared ceramic material can reach 73.68%,and a large number of silicon carbide nanowires appear on its surface and inside.3.To explore the influence of types of iron-containing compounds on the formation of silicon carbide,ferrocene,iron oxide,ferric nitrate and iron acetylacetonate were selected,and four iron-containing compounds were explored as sintering additives.The results show that ferrocene catalyzes the nucleation and growth of silicon carbide phase with the best effect,and when the amount of ferrocene is 1wt%,the crystal form of silicon carbide ceramics is best.