Research On The Cast Iron Inoculation Process Optimization

The effects of recarburization on the metallographic structure and mechanical properties of the original molten iron, and even the final castings were investigated under production conditions. Taking account of the production cost.the inoculation technique was combined with the low alloying treatment in the anufacturing of high quality castings. A new kind of inoculant was developed, and the effect of which on the structure and properties of high grade gray cast iron was investigated.The experiment result showed that the appropriative recarburizer can adapt the complicated environment of cupola melting. The application of recarburizer can decrease the usage of moderate cast pig iron, and, consequently improve the melting iron quality. Experimentation result indicated that,castings after recarburization have better metallographic structure and mechanical properties, that completely complies with the production technology requirement.All capabilities are qualified enough through better elements matching of the new low alloying treatment to meet the requirements of high-performance diesel engine. The stability of tensile strength and machining property were greatly improved, but the cost of production was reduced.Effeces of instant stream inoculation process on the cylinder head, flying wheel and engine body were systematically discussed. Experiment results showed that the instant stream inoculation process could increase the comprehensive mechanical properties and section sensitiveness. The adding amount should be proper, and should be determined by the casting type. An excess of adding amount would cause undense defects of the castings including inner shrinkage, or outer sink, and a high production costs.Experimental result indicated that, the CF inoculant could replace the ferro-molybdenum, ferro-nickel and silicon-barium inoculant. The tensile strength could steadily reach 280 MPa or more, by an adding amount of 0.5% CF inoculant. The tensile strength on the particular position of the WD615 cylinder lock and head castings itself could reach 280 MPa.The A type graphtie of assessment level four and fine pearlite could be obtained by CF inoculant. Processability of castings after inoculation was well. The production cost of castings was reduced, as a result of desuetude of ferro-molybdenum, ferro-nickel and other inoculant.