Bottom die used in the bottle at the bottom of the forming, material has the d-type graphite cast iron, heat-resistant nodular cast iron and heat resistant nodular cast iron, alloy elements, the casting hardness is 150-170 - hb, casting heat conduction performance is good, have good temperature and shaping, spheroidal graphite structure is more than 85%, advanced melting process, to ensure that the form of graphite evenly and mold in the process of using the stability of the mould material. D-type graphite cast iron, castings, 150-150 - hb hardness, ferrite is more than 80%, the pearlite is less than 15%, thus provides the mould deformation resistance, tensile strength of 290 mpa, and has good resistance to oxidation and thermal fatigue resistance.