Abstract：A dynamic indentation test device consisting of a titanium alloy pressure bar and a Vickers diamond indenter was designed. A momentum trap is introduced to avoid multiple loading due to a single pressure bar. This device can deliver an indentation load with pulse width of 80 μs and then is used to investigate the high-strain-rate response of quasi-brittle single crystal materials such as sugar and RDX crystals. Comparative experiments between single and multiple indentation loading were carried out for sugar crystals. the dynamic hardness of crystal sugar is approximately 5.18MPa. RDX single crystal is very prone to fracture and fragment under indentation loading and its dynamic hardness is 1.304MPa. Compared with RDX crystal, plastic deformation ability of sugar single crystal is better. Radial and circumferential crack of the indentation pit are observed using optical microscope. The crack growth mode of quasi-brittle crystal under dynamic indentation load is presented.
2017, Vol. 38 
