Specific crystallizer casting powder for sulphur free-cutting steel and production method thereof

A technology of mold powder and free-cutting steel, applied in the field of metallurgical auxiliary materials, can solve the problems of low interfacial tension, easy segregation of sulfides, and difficult separation, and achieve the effects of improving melting uniformity, increasing grinding time, and avoiding surface cracks

CN101982257AActive Publication Date: 2011-03-02HENAN TONGYU METALLURGY MATERIALS GRP
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2011-03-02
Patent Text Reader

Abstract

The invention discloses a specific crystallizer casting powder for sulphur free-cutting steel and production method thereof, mass percents of chemical components thereof are as follows: 29-35% of CaO, 25-30% of Sio2, 2-5% of MgO, 3-5% of Al2O3, 2-6% of Fe2O3, 5-11% of NaO?, 0-2% of Li2O, 5-9% of CaF2?, 0-5% of MnO, 0.5-2.0% of Al grey, 0-2% of B2O3, 5-11% of solid carbon, and allowance is building material adhesive and water. The sulphur free-cutting steel has low high-temperature strength and high crack sensitivity, and the casting powder should have properly high basicity. Basicity of a slag is improved, so that diffusion velocity is accelerated, and absorption of impurities in molten steel is benefited. So, improvement of basicity is an effective means for improving absorption of the impurities and control of surface longitudinal crack.
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Description

technical field

[0001] The invention belongs to the technical field of metallurgical auxiliary materials, in particular to mold mold powder specially used for sulfur-containing free-cutting steel and a manufacturing method thereof. Background technique

[0002] Sulfur-containing free-cutting steel is widely used because of its good cutting performance in the machining process, low tool force, easy chip breaking during cutting, good surface finish, and long tool life. Sulfur in steel mainly exists in the form of MnS in steel, because MnS inclusions cut off the continuity of the matrix and act as a source of stress concentration, making the chips easy to break, and the good lubrication effect reduces the wear of the tool, thereby improving the cutting of steel performance.

[0003] The following problems exist in the production of sulfur-containing free-cutting steel during continuous casting: 1) due to the low high-temperature strength of sulfur-containing free-cutting steel...

Examples

Embodiment 1

[0023] A special mold powder for sulfur-containing free-cutting steel, the mass percentage of its chemical composition is as follows: CaO33.5%, SiO 2 30.1%, Li 2 O 1.0%, NaO 8.5%, B 2 o 3 0.6%, F 8.3%, MgO 2.4%, Al 2 o 3 3.2%, Al + 0.8%, Fe 2 o 3 2.3%, C 6.8%. The balance is the material binder and moisture.

[0024] Mold flux physical properties: melting point 1065°C, viscosity 0.11Pa·S at 1300°C, melting speed 24 seconds.

Embodiment 2

[0026] A special mold powder for sulfur-containing free-cutting steel, the mass percentage of its chemical composition is as follows: CaO36.5%, SiO 2 32.1%, Li 2 O 1.1%, NaO 6.5%, B 2 o 3 0.2%, F 6.3%, MgO 2.4%, Al 2 o 3 3.5%, Al + 1.2%, Fe 2 o 3 2.0%, C 7.8%. The balance is the material binder and moisture.

[0027] Physical properties of mold flux: melting point 1045°C, viscosity 0.10Pa·S at 1300°C, melting speed 26 seconds.

Embodiment 3

[0029]A special mold powder for sulfur-containing free-cutting steel, the mass percentage of its chemical composition is as follows, CaO32%, SiO 2 27.5%, MgO 3.5%, Al 2 o 3 4%, Fe 2 o 3 4%;NaO+K 2 O 8%, Li 2 O 1%, CaF 2 +NaF 7%, MnO 2.5%, Al Ash 1.25%, B 2 o 3 1%. , 8% solid carbon, and the balance is binder and moisture.