Stress wave induced damage and fracture in impacted glasses

Abstract

The conditions for crack nucleation under impact loading were investigated systematically for four glasses which differ in their chemical composition, hardness and material density. Edge-on impact experiments were carried out with blunt steel cylinders within the velocity range from 20 m/s to 1000 m/s. The propagation of shock waves, of primary and secondary cracks and crack systems and the growing of crack systems from nucleated centers were observed by means of a Cranz-Schardin camera in a shadow optical arrangement

Penetration and failure of lead and borosilicate glass against rod impact

“…[15,[19][20], it is suggested that v F % ffiffi ffi 2 p c S . Similar results are concluded from edge-on impact tests with four different glasses [21,22]. These experiments considered a so-called damage velocity v D , which is determined by crack nucleation between the shock and fracture fronts.…”

Analysis of the Fragmentation of AlON and Spinel Under Ballistic Impact

“…Several theoretical treatments of the problem of stable crack propagation have predicted a terminal crack velocity of about 50% of the Rayleigh wave velocity c R [12][13][14], depending on Poisson's ratio of the material. These results have been confirmed experimentally for brittle amorphous materials, like PMMA [15] and different types of glass [16]. Ravi-Chandar and Knauss [17] concluded from their studies that the terminal crack velocity is not a fixed fraction of the Rayleigh wave speed and that this fraction is materialdependent.…”

Modelling of the adhesive layer in mixed ceramic/metal armours subjected to impact

“…Senf et al [8] and Strassburger et al [9] measured the dynamic propagation velocity of cracks in glasses and ceramics, and found values of v cracks in between 1/3 and 1/6 of u ceramic . Den Reijer proposed a value of 1/5 of u ceramic to fit the numerical simulations made by Wilkins [1].…”