High-strength composite salt core material for low-melting-point alloy casting, salt core and preparation method

The invention belongs to the technical field of casting, and particularly relates to a high-strength composite salt core material for low-melting-point alloy casting. The high-strength composite salt core material comprises, by mass, 70%-100% of water-soluble inorganic salt and 0%-30% of a reinforcement, wherein the water-soluble inorganic salt comprises one of low-melting-point salts including potassium nitrate and sodium nitrate, and at least one of high-melting-point salts including potassium chloride, sodium chloride, potassium bromide and sodium bromide, and positive ions of the low-melting-point slats are the same as positive ions of the high-melting-point salts. The invention further discloses a preparation method of a high-strength composite salt core, and an obtained salt core product. The prepared composite salt core has extremely high bending strength, excellent hygroscopicity and small volume shrinkage, and the comprehensive performance is excellent. In addition, the preparation technique of the h