Functionally graded electrical/thermal ceramic systems
Functionally graded electrical/thermal ceramic systems
复制标题
功能分级电/热陶瓷系统
DOI：
10.1016/s0955-2219(01)00165-0
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发表时间：
2001
影响因子：
5.7
通讯作者：
Christopher Murray
中科院分区：
文献类型：
--
作者：
A. Ruys;E. B. Popov;D. Sun;J. Russell;Christopher Murray
陶瓷-金属和陶瓷-陶瓷功能梯度材料(FGM)在热电转换器、梯度固体氧化物燃料电池、梯度压电材料、电绝缘接头、聚变反应堆的散热器和轻型航天器的热障蒙皮等假想应用中显示出良好的前景。大多数研究要么集中在功能梯度材料薄膜(直径为微米)上，要么集中在假想的功能梯度材料模型上。具有连续(非分层)梯度的大型块状功能梯度材料是上述应用的理想选择，然而，现有的块状功能梯度材料粉末加工技术提供的梯度控制很少，加工速度较慢。作者开发了一种新的工艺，叶轮干混，它提供了生产大范围可控连续梯度和成分的大体积功能梯度材料的可能性。在这篇论文中，首次发表了叶轮-干混过程的研究，制备了铜-碳化硅和不锈钢-碳化硅功能梯度材料。电子显微镜和元素分析表明，在几毫米的横截面上存在线性成分梯度。致密化采用真空烧结和静液压冲击成形。
Ceramic–metal and ceramic–ceramic functionally graded materials (FGMs) show promise for hypothesised applications such as thermoelectric converters, graded solid oxide fuel cells, graded piezoelectrics, electrically insulating joints, heatsinks for fusion reactors, and thermal barrier skins for lightweight spaceplanes. Most research has focussed either on FGM films (microns across), or modelling of hypothetical FGMs. Large bulk-FGMs with continuous (not layered) gradients are ideal for the above listed applications, however existing bulk-FGM powder-processing technologies give little gradient control and slow processing throughputs. The authors have developed a new process, impeller-dry-blending, which offers the possibility of producing large bulk-FGMs of a wide range of controllable continuous gradients and compositions. In this, the first published study of the impeller-dry-blending process, Cu–SiC and stainless steel–SiC FGMs were fabricated. Electron microscopy and elemental analysis revealed linear compositional gradients across cross sections of several millimetres. Densification was by vacuum sintering and hydrostatic shock forming.