Vanadium-titanium vermicular cast iron and production method thereof

The invention discloses vanadium-titanium vermicular cast iron and a production method thereof. The vanadium-titanium vermicular cast iron comprises the following compositios in percent by weight: 3.8-4.2% of carbon, 1.8-2.2% of silicon, 0.4-0.7% of manganese, 0.15-0.34% of vanadium, 0.05-0.08% of titanium, 0.1-0.3% of chromium, 0.03-0.06% of sulfur, 0.05-0.09% of phosphorus, 0.01-0.03% of residual magnesium, and the balance iron. The vanadium-titanium vermicular cast iron employs vanadium-containing pig iron as a raw material, and is not added with other precious metal elements. The produced vanadium-titanium vermicular cast iron possesses the characteristics of excellent mechanical properties, good wear resistant, thermal fatigue resistance, low production cost and the like. The pearlite content in the vanadium-titanium vermicular cast iron microstructure is 70% or more, the vermicular graphite rate is 70% or more, and on the aspect of mechanical properties, the tensile strength is 400 MPa-460 MPa, and the Brinell hardness is 200 HBS-240 HBS. The vanadium-titanium vermicular cast iron utilizes vanadium-containing pig iron as the raw material and is not added with other precious metal elements, therefore the production cost is reduced and the performances reach RuT450A requirements. The vanadium-titanium vermicular cast iron possesses good mechanical properties, wear resistance and thermal conductivity, is applicable to produce automobile brake drums, brake discs and other parts, and has wide market application prospect.