Inoculation Solutions Against Metallurgical Problems
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Copyright 2020 American Foundry Society https://doi.org/10.1007/s40962-020-00431-4
Abstract Inoculation can be used to fight many complex iron defects. Five cases will be developed to illustrate in different metallurgical conditions how beneficial some elements can be to solve specific metallurgical issues. •
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Inoculation solutions to fight chunky graphite in heavy-section castings in SGI: An example of the beneficial use of SB/RE-bearing inoculants associated with 10% Ba-bearing inoculant is given. Inoculation of solid solution-strengthened iron (SSFI): SSFI is well known to be difficult to inoculate, and a correct and consistent graphite shape is not easy to obtain. An efficient ‘‘package’’ has been proposed to a foundry producing SSFI, combining Ba-preconditioning and Bi/REbearing inoculation. Inoculation of Ni-resist iron: Ni-resist iron is very sensitive to chunky or degenerated graphite because of the high Ni-amount. Here is shown a case where chunky graphite has been found in a
Introduction Inoculation corresponds to the practice of adding a material in a small amount to liquid cast iron just before pouring to modify the iron solidification process. This inoculation step is usually compulsory to guarantee the final requested materials mechanical properties. The inoculation materials are normally made of a FeSi-alloy doped with different elements to guarantee a specific action. Among the noticeable effects of inoculation, the formation of nuclei support for graphite germination and matrix structure control are well known to impact positively the mechanical properties of
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foundry, where the problem has been solved using specific inoculants. Inoculation solutions for vertical centrifugal SG iron: An example of successful association of 10% barium inoculant associated with Bi/RE-bearing inoculation is presented on very-heavy-section rolls. Their effects are beneficial to mechanical properties of the bi-metallic material. Ba-inoculation to modify the slag composition: Slag build-up is a normal phenomenon in the metallurgical process but can, however, be a source of various problems. Here is given an example of use of a high-Ba inoculant facilitating de-slagging operations.
Keywords: inoculation, barium, bismuth, antimony, rare earth, chunky graphite, solid solution-strengthened ferritic ductile iron, Ni-resist iron, vertical centrifugal SG iron, slag build-up
the casting. This vision is likely to be quite restrictive as there are many concomitant benefits for inoculation practice and also they are becoming more and more key parameters to solve the challenges arisen by some emerging materials. In this article, five cases will be developed to illustrate the benefits of certain elements deliberately present in inoculant and useful to solve some metallurgical or process issues.
Action of the Elements Barium, Bismuth and Antimony in the Inoculation Role of Barium
This paper is an invited submission to IJMC selected from presentations at the 6th Keith Millis on Ductile Iron held on October 23–26, 201
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