Grain-boundary sliding in high-temperature ceramics: mechanical spectroscopy of high-purity magnesium oxide

高温陶瓷中的晶界滑动：高纯氧化镁的机械光谱

• 批准号: DP0450929
• 负责人: Prof Ian Jackson
• 金额: $ 16.02万
• 依托单位: The Australian National University
• 依托单位国家: 澳大利亚
• 项目类别: Discovery Projects
• 财政年份: 2004
• 资助国家: 澳大利亚
• 起止时间: 2004-01-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://dataportal.arc.gov.au/RGS/Web/Grants/DP0450929
• 关键词: Grain; boundary; sliding; temperature; ceramics

The demise of elastic behaviour in materials stressed at sufficiently high temperature limits the usefulness of ceramics for structural applications, and is also responsible for reduced wave speeds and associated attenuation of seismic waves in the Earth's interior. Yet the nature of the transition in fine-grained materials tested at high temperature from elastic through anelastic to viscous rheology remains poorly understood. Through a combination of mechanical testing by torsional forced oscillation/ microcreep methods of carefully fabricated and characterised specimens of polycrystalline MgO and associated micro-mechanical modelling we seek to clarify this fundamental and general aspect of high-temperature mechanical behaviour.

在足够高的温度下承受压力的材料的弹性行为的消失限制了陶瓷在结构应用中的用途，也是导致地球内部波速降低和相关的地震波衰减的原因。然而，在高温下测试的细晶材料中，从弹性到滞弹性再到粘性流变学的转变的本质仍然知之甚少。通过用扭转强迫振荡/微蠕变方法对经过精心制作和表征的多晶氧化镁样品进行的力学测试和相关的微观机械模型相结合，我们试图阐明高温力学行为的这一基本和一般方面。