Potential of the Sinter-HIP-technique for the Development of High-temperature Resistant Si3N4-ceramics
Potential of the Sinter-HIP-technique for the Development of High-temperature Resistant Si3N4-ceramics
复制标题
烧结热等静压技术开发耐高温氮化硅陶瓷的潜力
DOI：
10.1016/s0955-2219(99)00106-5
复制
发表时间：
1999
影响因子：
5.7
通讯作者：
R. Oberacker
中科院分区：
文献类型：
--
作者：
M. Hoffmann;A. Geyer;R. Oberacker
通过两步烧结热等静压工艺，用烧结添加剂 Y2O3 和 SiO2 致密化氮化硅陶瓷。制备了三种添加剂含量在 2 至 7 wt% Y2O3 之间的组合物，以研究加工条件对机械性能的影响。几乎完全致密化（>98.5%）所需的最低添加剂含量仅为 2 wt% Y2O3。然而，致密化仅限于一定的 Y2O3/SiO2 比率。富含添加剂的样品在室温下的平均强度高达 800 MPa，在 1400°C 时会降低。仅含有 2 wt% Y2O3 的材料的室温强度约为 500 MPa，但在 1400°C 下强度没有下降。较低的强度与脆性的显着增加相关，添加剂含量的降低表明组合物 2/0 的断裂韧性仅为 2·5 MPam1/2。研究的材料在 1400°C 下表现出相对较高的抗蠕变性，蠕变速率低至 1·5×10−9s−1。
Silicon nitride ceramics were densified with the sintering additives Y2O3and SiO2by a two-step sinter-HIP-process. Three compositions with additive contents between 2 and 7 wt% Y2O3were prepared to study the influence of the processing conditions on the mechanical properties. The minimum additive content required for nearly complete densification (>98.5%) was only 2 wt% Y2O3. However, densification was limited to certain Y2O3/SiO2ratios. The additive-rich samples revealed a mean strength at room temperature up to 800 MPa which degrades at 1400°C. The material with only 2 wt% Y2O3has a room temperature strength of ∼500 MPa, but no strength degradation up to 1400°C. The lower strength correlates with a pronounced increase in brittleness with a decreasing additive content indicated by a fracture toughness of only 2·5 MPam1/2for composition 2/0. The investigated materials exhibit a relatively high creep resistance at 1400°C with creep rates down to 1·5×10−9s−1.
影响因子：
5
作者：
M. Hoffmann
通讯作者：
M. Hoffmann