inoculants

　　There are many types of inoculants, and the more commonly used ferroalloy inoculants are 75 ferrosilicon inoculants. Nowadays, the demand for thin walls in castings is getting higher and higher, and the requirements for the use of inoculants are also stricter. Among them, inoculants with rare elements are better, and carbon inoculants have also been used in large quantities in recent years. When choosing an inoculant, in addition to doing a lot of research, you also need to know what the effects of other inoculants are. So what exactly does an inoculant have? Learn how to use the inoculant as soon as possible!

　　Ferrosilicon inoculant

　　75 Ferrosilicon is the more commonly used inoculant. The content of aluminum and calcium play an important role in the inoculation effect. According to reports, ferrosilicon without aluminum and calcium has little or no use for the inoculation of gray cast iron. It is generally believed that in molten iron, aluminum and calcium will react with oxygen and nitrogen to form compounds with high melting points, which become the core of graphite crystals. Moreover, after adding the inoculant, local silicon-rich micro-regions can be formed in the molten iron, which is conducive to graphite precipitation. When purchasing ferrosilicon for incubation, the content of aluminum and calcium cannot be ignored.

　　Strontium-containing ferrosilicon inoculant

　　Strontium-containing ferrosilicon has a strong ability to eliminate white holes, which is particularly beneficial to improve the shape and distribution of graphite in thin-walled castings, so that the spacing of tissues at different thicknesses is smaller, and the supercooled structure is only seen on the surface of the casting.

　　Barium-containing ferrosilicon

　　Barium-containing ferrosilicon also has a strong ability to promote graphitization, which can improve the shape and distribution of graphite in thin-walled castings, and it also has the function of slowing down the gradual reduction of incubation. The dosage of 75 ferrosilicon can also be used for treatment.

　　Zirconium-containing ferrosilicon inoculant

　　Zirconium is used for deoxidation, which is beneficial to improve the fluidity of molten iron, reduce the tendency of cast iron to white mouth, and promote uniform and fine A-type graphite. And it also slows down the gestational decline.

　　Silicon barium alloy inoculant

　　Using a silicon-barium alloy containing 20-30% barium as an inoculant can reduce the white-mouth criticality of cast iron with high quality, and at the same time maintain the inoculation effect for a period of about 30 minutes, which is especially suitable for large castings. During processing, the amount of alloy added is about 0.1%

　　Rare earth inoculant

　　Rare earth mixed metals and rare earth ferrosilicon and other inoculants containing rare earth metals, when added in an appropriate amount, are very useful for inoculation. Its effect can be several times that of 75 ferrosilicon, which can effectively eliminate white mouth and slow down the decline of inoculation.

　　Carbon inoculant

　　Carbonaceous inoculants are mainly used for pretreatment of molten iron before inoculation, and are generally crystalline carbonaceous materials. For gray cast iron, 85-90% alloy silicon carbide is better, and crystalline graphite is also effective. The added amount is generally 0.75~1.0%, and a better value should be obtained based on the test results. Understanding the application effects of these inoculants can be more efficient and effective when choosing an inoculant!