The polycrystalline diamond compact with 58 mm diameter was synthesized on domestic cubic press.Scanning acoustic microscope(SAM)analysis showed that there were no defects such as delamination,crack and non-uniform thickness of PCD layer in batch samples.Electrical conductivity and cutting test indicated that the cutting speed and wear resistance of the 25 μm grain size 58GD-025PDC and 58GM-253PDC with mixed grain size was superior to other competitors.