Effect of load in scratch experiments on soda lime silica glass

Effect of scratching speed on deformation of soda–lime–silica glass

“…This happened because the maximum shear stress (τ max ∼ 14 GPa) calculated following [24] as a function of the effective applied normal force, P eff = P (1 + μ 2 ) 0.5 , increased with scratching speed (Fig. 7f) and its magnitude was much greater than the theoretical shear strength τ theor ∼ 3-6 GPa of SLS glass [20,25,26]. Based on the present experimental evidences, two qualitative models are schematically presented for surface tensile cracks formed and interacted to create a probable zone for micro-chipping, Fig.…”

“…The experimental details have been already reported elsewhere [19][20][21] and hence will be only briefly mentioned here. The scratch tests were performed on mirror polished 25 × 25 × 1.40 mm soda-lime-silica glass slides (Blue Star, Kolkata, India) in air under ambient laboratory conditions at a constant applied normal load (P ) of 5 N with scratching speeds (v) of 100, 200, 500 and 1000 µm s −1 with a scratch tester (Model TR-102-M3, Ducom, Bangalore, India) equipped with a Rockwell C diamond indenter with 200-µm tip radius.…”

New observations on scratch deformations of soda lime silica glass

“…3). The corresponding SEM [26,27,29] photomicrographs for an applied load of 5 N showed the genesis and the mode of propagation of the edge cracks in tracks made at 100 ( Fig. 4(a)) and the damage in the scratch track much less for 1000 μm/s ( Fig.…”

“…A scratch tester (Model TR-102-M3, Ducom, Bangalore, India) equipped with a Rockwell C diamond indenter with~200 μm tip radius was used for this purpose. Further details may be found in [26][27][28][29]. A compound force transducer is coupled with the scratch tester which can measure both normal load (P) and the tangential force (F).…”

“…The scratching speed, the angle, the radius as well as the shape of cutter tip along with the applied normal load affect the critical condition for growth [22] of various sub-surface cracks in a wide variety of glasses when measured by different techniques [23][24][25]. We have recently reported the influence of normal load on the material removal mechanisms and the degradation of the nanomechanical properties inside the scratch groove of a soda lime silica (SLS) glass [26][27][28][29]. Very recently [29] we reported the experimental observation of the inverse power law dependencies of width, depth, wear volume of scratch grooves and the corresponding wear rate of SLS glass on the scratching speed (v) when the applied normal load was kept constant at a low value of 5 N. Extending our previous work [29] here we report the development of a new, simple model that explains the scratch behavior of SLS glass studied at three different normal loads when it is scratched with a blunt diamond indenter of~200 μm tip radius at three different scratching speeds.…”