The addition of SiC particles into a MoSi2-doped ZrB2 matrix: Effects on densification, microstructure and thermo-physical properties
The addition of SiC particles into a MoSi2-doped ZrB2 matrix: Effects on densification, microstructure and thermo-physical properties
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DOI：
10.1016/j.matchemphys.2008.07.091
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发表时间：
2009-02
影响因子：
4.6
通讯作者：
F. Monteverde
中科院分区：
文献类型：
--
作者：
F. Monteverde
研究了MoSi 2掺杂ZrB 2的SiC颗粒的致密化、显微结构和性能。在ZrB 2中加入MoSi 2作为烧结助剂。增强的致密化是由伪二元反应驱动的，该反应涉及ZrB 2和瞬态Mo硼化物，其作为MoSi 2与ZrB 2颗粒上的表面氧化物之间的反应产物而形成。ZrB 2晶粒具有核-环结构。室温强度可达800 MPa。在1500°C（空气中），强度下降到240 MPa。与ZrB 2（室温下为3.4MPam）相比，SiC的加入增加了断裂韧性（室温下为4.1MPam）。随着SiC的加入，ZrB 2的抗热震性也有所提高。实验测得的临界热震温差从ZrB 2的330°C提高到SiC的385°C。SiC的加入也降低了ZrB 2的氧化速率。研究结果表明，MoSi 2作为烧结助剂对ZrB 2基材料的致密化和性能有着积极的影响。
The densification, microstructure and properties were studied for MoSi2-doped ZrB2-containing SiC particles. MoSi2is added to ZrB2as sintering aid. The enhanced densification was driven by a pseudo-binary reaction involving ZrB2and transient Mo borides, which were formed as products of the reaction between MoSi2and the surface oxides on the ZrB2particles. The ZrB2grains had a core–rim microstructure. Room temperature strengths up to 800MPa were measured. At 1500°C (in air), strengths decreased to 240MPa. The addition of SiC increased the fracture toughness (4.1MPamat RT), compared to ZrB2(3.4MPam at RT). The resistance to thermal shock of ZrB2also increased with the addition of SiC. The measured critical thermal shock temperature difference increased from 330°C for ZrB2to 385°C when SiC was added. The addition of SiC also decreased the oxidation rate of ZrB2. The investigations gave evidence of the beneficial influence of MoSi2as sintering aid on densification and properties of ZrB2-based materials.