Low-magnesium barium-containing spheroidized cored wire

Abstract

The invention discloses a low-magnesium barium-containing spheroidized cored wire, and belongs to the technical field of ferrous metal materials. The core powder comprises the components of, in percentage by mass, 8%-12% of Mg, 45%-60% of Si, 1.5%-2.5% of RE, 5%-10% of Ba, 1.5%-3% of Ca, 0.5%-1.5% of MgO, 1.0%-1.5% of Al and the balance Fe. According to the low-magnesium barium-containing spheroidized cored wire, the spheroidizing function and the inoculation function are integrated, inoculation of cored wires is not needed any more, thus the magnesium content is reduced, the wire feeding timeof a small ladle with the weight being 500 kg or below is stably controlled to be 24-32 s, and the problem that due to the fact that the wire feeding time is too short, magnesium absorption is unstable in the small ladle spheroidizing process is solved; and the nodulizing cored wire is used for wire feeding and nodulizing, the content of residual Mg in molten iron is more stable than that of an in-ladle pouring method, and nodulizing of ductile iron is poor and pore waste is lower.

Description

technical field [0001] The invention relates to a cored wire, in particular to a low-magnesium and barium-containing spheroidized cored wire, which belongs to the technical field of ferrous metal materials. Background technique [0002] At present, the investment casting precision casting nodular cast iron usually adopts a small spheroidizing bag of 250kg-500kg, and the spheroidizing process is carried out by punching into the bag. With the improvement of environmental protection requirements, it has become a trend to gradually replace the traditional spheroidization process with the feeding method. [0003] Under the constraints of the domestic cored wire specification φ13, the current spheroidized cored wire JB / T13472-2018 is adopted. Because the Mg content is as high as 21%-30%, the spheroidization time of this 250-500kg small spheroidized bag Less than 15s, too short spheroidizing time and violent spheroidizing reaction, resulting in extremely unstable residual Mg conte...

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Problems solved by technology

[0003] Under the constraints of the domestic cored wire specification φ13, the current spheroidized cored wire JB / T13472-2018 is adopted. Because the Mg content is as high as 21%-30%, the spheroidization time of this 250-500kg small spheroidized bag Less than 15s, too short spheroidizing time and violent spheroidizing reaction, resulting in extremely unstable residual Mg content in molten iron in small spheroidizing ladles

Preliminary tests have shown that the residual Mg content of molten iron is 0.035-0.069%, which leads to unstable spheroidization. Investment casting often has residual Mg lower than 0.040% and worm-like graphite phenomenon occurs, and Mg content higher than 0.06% sometimes causes castings stomatal problem

[0004] The existing cored wire has the following deficiencies: (1) When producing nodular cast iron by small-scale spheroidizing and feeding wire spheroidization, the residual Mg in molten iron is unstable due to the short feeding time; (2) The residual Mg in molten iron is too low to cause wormlike Graphite, while too high will cause casting porosity

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