Quantitative Determination of Stress and Strain Distributions During High Axial Compression of Aluminium With the Aid of Small Ruby Particles

Line shift measurements of the sharp R₁ ruby fluorescence line with respect to a neon reference line are used for the determination of quantitative stress distributions during high axial compression of cylindrical samples of aluminium between two transparent sapphire anvils. At the sample-anvil interface small ruby particles are embedded in the aluminium surface as optomechanical sensors for local stress and strain measurements. The experimental results are used to verify computer calculations based on the finite element method. The measurement technique was recently described by Brouha et al. [5, 6]. In this paper some modifications and new results will be presented and the use of pure sapphire anvils with a stress-sensitive top layer of ruby obtained by implantation of Cr³⁺ ions will be discussed.