摘要
本文研究了α-SiC微粉的强化球磨与热压烧结工艺及性能。通过对热压条件—显微结构—产品性能的实验与分析,得出了适合于所研制材料的工艺条件。在1950℃,30MPa,保温保压60min的热压条件下,烧结体相对密度达99％以上,室温抗弯强度超过1400MPa,热膨胀系数为4.66×10^(-6)℃^(-1),硬度HRA>94,并具有优良的抗热震性。研究表明,球磨杂质WC及Fe等的介入,改善了SiC陶瓷的烧结性能,加快了致密化进程,并提高了SiC的抗弯强度。
The intensive ball-milling of α-Sic micropowders and their hot-pressed sintering bchaviour are studied in this paper. Based on the experiments and analyses of the relationships under hot-pressing conditions, microstructures, and properties, the suitable technique condition for the material is obtained. The sample hot-pressed at 1950℃ for 60 minutes under pressure of 30MN/m^2acquires the following properties: relative density over 99%, flexure strcngth at room temperature is over 1400 MN/m^2, thermal expansion coefficient is 4.66 × 10^(-6)/℃, rockwell hardness HRA is over 94, and it has cxcellent thermal-shock resistance. The results show that WC and Fc have improved the sintering bchaviour of Sic ceramics, accelerated the densifieation and increased the flexure strength.
关键词
碳化硅
高强度陶瓷
热压
金属陶瓷
silicon carbide, high-strength ccramic, hot-press, ccramctallics
