The microstructure, mechanical properties and heat treatment process of high chromium cast iron were studied. A composite modifier composed of rare earth ferrosilicon, calcium silicon, ferrosilicon and a small amount of low melting point metal particles was used to improve the morphology of eutectic carbide, refine the matrix structure and improve the grain boundary state of high chromium cast iron, so as to improve the comprehensive properties of high chromium cast iron.
- the composite modification of high chromium cast iron can not only refine the grain of matrix structure, but also significantly improve the size, morphology and distribution of eutectic carbides, and change from continuous large-size fiber like and cluster like to isolated scattered small block like. The isolation degree is increased and significantly refined.
- compound modification can obviously improve the impact toughness without reducing the hardness of high chromium cast iron.
- the composite modifier composed of rare earth, calcium, silicon and a small amount of low melting point metals can produce a variety of compounds higher than the flame point at above 1450 ° C, which can be used as the crystallization core of, and promote the formation of a large number of small particle crystals.