Effect of Si,Cr and Cu on the Corrosion Resistance to Aluminum Melt of Cast Iron Protector Tube Used for Measuring Temperature of Aluminum Melt

Orthogonal design has been adopted in this experiment. By adding Si,Cr and Cu into the cast iron, the microstructure of cast iron protector tube used for measuring temperature of aluminum melt can be refined. The influence of alloying element content and the microstructure of cast iron on corrosion resistance of the cast iron to aluminum melt has been investigated. The experimental results show that, on the base content of alloying elements in the cast iron, increasing the content of Cu to 0 29%～0 89% and Si to 2 49%～3 09 % will improve corrosion resistance of the cast iron; increasing the content of Cr to 0.47%～1.49% and Si to 1 89%～2 49% will decrease corrosion resistance of the cast iron. Enhancing volume fraction of the flaky graphite and the slim flaky pearlite will improve corrosion resistance of the cast iron.