On the low velocity impact behaviour of glass plates

Abstract

Circular plates of float glass with thicknesses between 3 mm and 12 mm and clamped at a radius of 65 mm have been impacted with a 3 mm diameter hardened steel ball travelling at velocities in the range of 10-50 m S-l. The fractures can be classified as Hertzian ring cracks at the contact zone with or without conical fractures; crushed impact zones on the front face which may be accompanied by cone cracks, median, radial and lateral cracking and in some cases star cracks propagating from the rear face. Examples of these will be described together with a qualitative predictive analysis for their occurrence as a fknction of impact velocity, plate thickness and surface condition. Of particular interest is the observation of crack bifurcation within the cone fractures in plates of thicknesses below 6 mm.

The vulnerability of residential window glass to lightweight windborne debris

“…Bole [25] tested annealed, heat strengthened, and tempered glass using 2 × 4 timber missiles of 2.0 kg (4.5 lb), 4.1 kg (9 lb), and 8.2 kg (18 lb), and found that missiles of different mass but the same kinetic energy produced different results. Other related studies include [26][27][28].…”

Predicting the low-velocity impact behavior of polycarbonate: Influence of thermal history during injection molding

“…It was also observed that the penetration velocity for the 5.85 and 3.0 mm thick plates equaled 80 m/s and 65 m/s, respectively. Mckenzie et al [7] performed a series of impact tests with various impact velocities (10-50 m/s) on circular PC plates with thicknesses between 3 mm and 12 mm. They identified a number of failure mechanisms in the plates and constructed a fracture map which incorporates the effect of plate thickness and impact velocity.…”

“…The impact response of PC has been extensively studied in the literature by experimental research works, ranging from high velocity impacts [4][5][6][7][8][9] by means of gas gun impact tests to low velocity impacts [1,2,10,11], and by means of falling weight tests or Izod impact tests. Shah [4,5] carried out low velocity single and multiple impact tests on a thin PC armor plate.…”

Large-scale 3D modeling of projectile impact damage in brittle plates

“…Ring cracks are characterized by their average radius which is measured from the central impact point. Both conical and ring cracks are ubiquitous features of brittle impact damage and have been observed in impact experiments on a variety of different brittle materials including glasses (Knight et al, 1977;Ball and McKenzie, 1994), nominally brittle polymers (Hsieh et al, 2004), and ceramics (Bowden and Field, 1964;Evans and Wilshaw, 1977;Evans et al, 1978;Maekawa et al, 1991;Sherman and Brandon, 1997;Sherman, 1997Sherman, , 2000Sherman and Ben-Shushan, 1998;Normandia, 2004;Iyer, 2007;Brennan et al, 2010;Deshpande et al, 2011).…”

“…In order to gain insight into this problem, there has been a strong effort over the last fourty years to study impact damage through plate impact experiments where the cracking patterns were analyzed in recovered specimens (Bowden and Field, 1964;Evans and Wilshaw, 1977;Knight et al, 1977;Evans et al, 1978;Maekawa et al, 1991;Ball and McKenzie, 1994;Sherman and Brandon, 1997;Sherman, 1997Sherman, , 2000Sherman and Ben-Shushan, 1998;Normandia, 2004;Hsieh et al, 2004;Iyer, 2007;Deshpande et al, 2011). A key finding of these studies is that although highly complex, the cracking patterns resulting from impact loads can sometimes be decomposed into a small set of characteristic fracture modes whose propagation paths follow simple trajectories.…”