A kind of spheroidizing inoculation treatment process of nodular cast iron

Abstract

A nodulizing and inoculation process for nodular cast iron, comprising the following steps: step 1, adding 1% of nodulizing agent, 0.2% of silicon barium inoculant, 0.3% of long-acting inoculant, and weight to a pit of a nodulizing ladle in sequence; and step 2, pouring molten iron into another pit from a furnace, adding 0.15%-0.3% of silicon barium inoculant during tapping, and adding 0.1%-0.2% of stream inoculant during pouring, the molten iron obtained after nodulizing comprising no more than 0.012% of S and 0.040+ / -0.004% of Mg in order to ensure nodulizing.

Description

technical field [0001] The invention belongs to the field of metallurgy, and in particular relates to a spheroidizing inoculation treatment process of nodular cast iron. Background technique [0002] As early as the 1950s, many casting professionals proposed to solve the shrinkage cavity and shrinkage defects of ductile iron by rationally using graphite self-expansion. But so far, few people can use it flexibly. [0003] They believe that the stronger the inoculation effect, the more favorable the graphitization; the larger the graphitization expansion, the better the self-feeding effect. It is not known that the time of graphite expansion will affect the feeding effect, and some people even advocate that technological measures should be taken to advance graphitization expansion, balance expansion and contraction in the initial stage of solidification, and reduce external feeding shrinkage, thereby reducing the size of the riser the goal of. But in fact, the external feed...

AI Technical Summary

Problems solved by technology

But in fact, the external feeding conflicts with the expansion of graphite, and shrinkage defects are more likely to occur

Images