This paper explores the compressive responses of alumina ceramics subjected to various levels of pre-damage via internal cracking. Pre-damage is achieved by subjecting the samples to thermal shock. Mechanical loading is performed using a load frame for quasi-static strain rates and a Kolsky bar for dynamic strain rates. Digital image correlation is used to obtain two-dimensional strains alongside independently measured applied stresses. Data acquisition used in this study allows for the calculation of apparent elastic moduli as a function of strain. This allows for the study of change in mechanical response with strain, strain-rate, and level of pre-damage. There is a complex interaction between pre-damage and compressive loading, leading to mechanical damage accumulation being divided into three stages rather than a single damage accumulation function. It was also found that shear modulus change was more indicative of physical failure phenomena during loading than Young’s modulus or Poisson’s ratio changes.

本文探讨了氧化铝陶瓷通过内部裂纹经受不同程度的预损伤后的压缩响应。通过使样品经受热冲击来实现预损坏。使用准静态应变率的负载框架和动态应变率的Kolsky条执行机械加载。数字图像相关用于获得二维应变以及独立测量的施加应力。本研究中使用的数据采集允许计算视在弹性模量与应变的函数。这样就可以研究机械响应随应变，应变率和预损伤程度的变化。破坏前和压缩载荷之间存在复杂的相互作用，导致机械损伤累积被分为三个阶段，而不是单个损伤累积函数。还发现，剪切模量变化比杨氏模量或泊松比变化更能说明加载过程中的物理破坏现象。