汉麻秆基生物质陶瓷用纯炭坯体的制备与分析

Preparation and Analysis of Pure Carbonaceous Preforms for Biomorphic Ceramics from Hemp Straw

以汉麻秆芯炭粉为原料,采用干压成型工艺制备了生物质碳化硅陶瓷用多孔纯炭坯体,通过截面密度分析、SEM以及压汞测试等手段,对纯炭坯体的密度、显微结构和孔隙特征进行了分析。结果表明,成型压力在110MPa以下时,炭坯密度随压力升高而增加,达到110 MPa后密度不再增加;成型坯体截面密度分布及显微分布均匀;压汞测试表明,压力为35 MPa时所得炭坯的孔径主要介于1～80μm之间,具备制备高质量碳化硅陶瓷的理想条件。

Carbon powder from hemp straw was used as raw material,which was formed into pure carbonaceous preforms for reaction bonded silicon carbide（RB-SC） by dry pressing.These preforms were characterized according to their vertical density profile,microstructures and pore characteristics.Experimental results showed that the density of the preforms increased with increasing pressure until it reached 110 Mpa.When the pressure was 35 Mpa,pure carbonaceous performs with homogeneous pore distribution and microstructure characteristics could be obtained,and the pore size was mainly between 1 μm and 80 μm,which indicates that high quality RB-SC could be obtained by infiltrating the preforms prepared by dry pressing.