Field‐Assisted Densification of Superhard B6O Materials with Y2O3/Al2O3 Addition
Field‐Assisted Densification of Superhard B6O Materials with Y2O3/Al2O3 Addition
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添加 Y2O3/Al2O3 的超硬 B6O 材料的场辅助致密化
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
I. Sigalas
中科院分区：
文献类型：
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作者：
M. Herrmann;H. Kleebe;J. Raethel;K. Sempf;S. Lauterbach;M. Müller;I. Sigalas
B6 O是超硬材料的可能候选者，在单晶上测量的硬度为45 GPa。到目前为止，这些材料的致密化只能在高压下进行。然而，最近发现不同的氧化物可以用作有效的烧结添加剂。在这项工作中，除了Y2 O3/Al 2 O3的致密化行为作为施加压力的函数，其微观结构的演变，以及由此产生的机械性能的影响进行了研究。结果表明，材料的致密化与压力有很强的相关性，材料呈现出特征的三重结结构，其中充满了由B_2O_3、Al_2O_3和Y_2O_3组成的非晶残留物，而沿沿着内部界面没有观察到非晶晶界膜。机械测试显示平均硬度为33 GPa，断裂韧性为4 MPam 1/2，强度值为500 MPa。
B6O is a possible candidate of superhard materials with a hardness of 45 GPa measured on single crystals. Up to now, densification of these materials was only possible at high pressure. However, recently it was found that different oxides can be utilized as effective sintering additives. In this work the effect of addition of Y2O3/Al2O3 on the densification behaviour as a function of applied pressure, its microstructure evolution, and resulting mechanical properties were investigated. A strong dependence of the densification with increasing pressure was found. The material revealed characteristic triple junctions filled with amorphous residue composed of B2O3, Al2O3 and Y2O3, while no amorphous grain-boundary films were observed along internal interfaces. Mechanical testing revealed on average hardness of 33 GPa, a fracture toughness of 4 MPam1/2, and a strength value of 500 MPa.