Compared with gray cast iron, graphite in vermicular graphite cast iron is short and thick, curved and worm like. Because the density of vermicular graphite cast iron (i.e. the ratio of width and length of graphite shape i/d) is much larger than that of flake graphite in gray cast iron, vermicular graphite cast iron is also called dense graphite cast iron.
Vermicular graphite cast iron has good comprehensive properties, and its mechanical properties are obviously better than that of gray cast iron; Its heat conduction, vibration absorption, casting and processing properties are better than those of nodular cast iron, and it is known as a new type of cast iron. However, because the graphite morphology in vermicular graphite cast iron is between flake graphite and spheroidal graphite, it is difficult to control the graphite morphology in the. Therefore, the stability of vermicular cast iron production has become a difficult point in the quality control of vermicular cast iron. The technology of vibration was applied to the production of vermicular graphite cast iron, and the transformation law of microstructure and properties of vermicular graphite cast iron by vibration lost foam casting was discussed.
The existing research results show that the molten iron treatment temperature, sample wall thickness and vibration process parameters are the key process parameters to be controlled in the process of vibration lost foam casting. Therefore, in order to produce qualified castings, it is necessary to select appropriate process parameters for vibratory lost foam casting.