炭黑对熔融沉积成型3D打印碳化硅陶瓷显微结构和力学性能的影响OA

Pressureless sintered silicon carbide(SSiC)ceramics have broad application prospects in aerospace and other fields due to their excellent mechanical properties and thermal stability.In this study,SiC ceramics were prepared by fused deposition modeling(FDM)combined with pressureless solid-state sintering.The effects of carbon black specific surface area(10,80,150,and 230 m2/g)and content(2.0%,2.5%,3.0%,3.5%,and 4.0%,mass fraction)on the printing performance as well as the microstructure and mechanical properties of the sintered bodies were systematically investigated.The results show that when the specific surface area of carbon black is 150 m2/g and the content is 3.5%,feedstock ensures extrusion stability while achieving good shape retention.Under these conditions,the green body density reaches 2.18 g/cm3,and the flexural strength is(16.2±2.0)MPa.Too low specific surface area or insufficient content of carbon black leads to an incomplete carbothermal reduction reaction;whereas too high specific surface area or excessive content induces carbon black agglomeration,thereby inhibiting the densification process.After pressureless sintering at 2 150℃,when the specific surface area of carbon black is 150 m2/g and the content is 3.5%,the silicon carbide ceramic achieves a density of 3.02 g/cm3,a flexural strength of(344.0±52.0)MPa,and a hardness of(24.2±1.2)GPa.Using this process,various complex components were successfully fabricated using this process.This study provides a new approach for the fabrication of complex silicon carbide components by fused deposition modeling.