Unit Experimental Study on Impact Crushing Rock of the Microcoring PDC Bit

Table 1

Primary physical parameters of 3 rock samples.

Rock	Uniaxial compressive strength (MPa)	Shear strength (MPa)	Internal friction angle (°)	Elastic modulus (GPa)	Poisson’s ratio	Density(g/cm^3)
Sandstone	67.548	13.56	38.03	11.54	0.062	2.42
Limestone	105.951	17.72	43.62	31.2	0.171	2.46
Granite	126.519	13.7	45.29	31.78	0.118	2.73