Abstract
Three-dimensional finite element analysis for Vickers indentation on soda-lime glass was performed. The time-dependent stress distributions around and below the contact area during the indentation cycle, especially at the end of loading and at the beginning of the unloading phase, were investigated in detail. The results indicated that when the indentation depth was set to 2μm, at the corners of the indentation from beginning unloading the tensile stress increases dramatically and reaches the maximum value. It can be predicted that the radial cracks nucleate mostly from beginning of unloading at the shoulders of the indentation and propagate along the diagonal of the impression. Furthermore, the tensile stress below the contact surface increases considerably from unloading, which may explain why the lateral cracks nucleate from unloading half cycle. The analytical results were in good agreement with the experimental results.
