A long-term inoculant is one that includes anti-degradation components like barium and strontium. During the casting process, it functions as a silicon-barium inoculant. The presence of barium helps prevent the degradation of the seed and enhances the amount of ferrite. Barium ferrosilicon not only possesses excellent anti-rot characteristics but also effectively prevents white casting. The long-term seed material, known as silicon-barium seed material, is created by combining silicon powder and barium powder in specific ratios and smelting them in a high-temperature furnace. This additive is used in the casting process at foundries, where it aids in graphitization, reduces the likelihood of white casting, enhances the morphology and distribution of graphite, increases the number of eutectic groups, and improves the matrix structure. Its effectiveness lasts for a short duration after inoculation, approximately 5-8 minutes.
Composition Index for Silicon-Barium Inoculant:
- Ba: 1-2%, Ca: 1-2%, Si: 70-72%, Al: 1-2%
- Ba: 4-6%, Ca: 1-2%, Si: 65-70%, Al: 1-2%
- Ba: 2%-5%, Ca: about 1.5%, Si: 68%-72%
Standard particle sizes for Long Term Inoculant (Silicon Barium Inoculant) are: 0.1-0.4mm, 0.2-0.7mm, 1-3mm, and 3-6mm.
