Response of inherently brittle materials on higher loading rates

Abstract

Abstract. Generally, there are components loaded in a wide spectrum of loading rates, however most of design work is based on the data obtained using quasi-statical and uniaxial loading conditions. In case of inherently brittle materials the situation is all the more complicated because of their brittleness. There is a lack of experimental data and knowledge base of material response at loading in the range between quasi-static and ballistic loading rates.Cast basalt and soda-lime glass were the main experimental materials used in this investigation as a representative of natural based and structural brittle materials. These materials are widely used in civil industry as a building and decorative material, in chemical industry for transport of chemicals and in mining industry for transportation of powders (e.g. coal).Application in extreme conditions and safety requirements, in particular, raise an issue of fracture behaviour at higher loading rates. The main aim of the contribution is to investigate influence of strain rate on fracture resistance and to analyze response of the microstructure to high strain rate loading including the change of mechanical properties. The fractographic analysis of fracture surfaces was employed in the investigation with the aim to identify changes in fracture behaviour.

Material grain size and crack size influences on cleavage fracturing

“…Krafft et al [39] had commented previously on the importance of the strain rate in accounting for CVN impact test results. Chlup et al [40] have described application of higher strain rate testing to more brittle cast-basalt and soda-lime glass materials. Otherwise, equation (3.3) provides a quantitative description of the DBTT for a notched impact test [41,42] analogous to that given by Cottrell [12] and Petch [13].…”

Fracture response of SiOC-based composites on dynamic loading

“…Above this speed the inertia caused higher dynamic effects, making the test curves difficult to evaluate. This phenomenon was reported in work of Chlup et al 28 The three-point bending configuration with the span of 22 mm was used. The specimens were unnotched and tested in two basic orientations: in-plane (i.e.…”