The figure shows the matrix structure of gray prayer iron prepared under different vibration frequencies. Among them, figures (a) – (d) are the matrix structure diagrams of grey cast iron prepared at vibration frequencies of 0, 35, 50 and 100Hz respectively.
It can be seen from the figure that the flake spacing of pearlite in EPC grey cast iron without vibration is large, and the alloy matrix contains a small amount of carbide, as shown by the arrow in figure (a). When vibration is applied to the lost foam casting of grey cast iron, the carbides in grey cast iron disappear, but the lamellar spacing of pearlite shows two trends. When the vibration frequency is 35Hz, although pearlite with large lamellar spacing appears around a few graphite in grey cast iron, the lamellar spacing of most pearlite is small, and the length of lamellar cementite decreases; When the vibration frequency increases to 50Hz, the distance between pearlite sheets in the alloy increases, and the length and thickness of cementite sheets in pearlite become shorter and larger; When the vibration frequency increases to 100Hz, a small amount of granular pearlite appears in the alloy.