30results about How to "Good shape of graphite" patented technology

A method for casting a box-type complex water-cooling exhaust pipe by using an iron mold coated sand is disclosed. By using the water-free coated sand mold, the method helps to realize rapid cooling and mold filling, eliminate the defects of nail-passing-hole structure loosening and casting deformation often happening in the water-cooling exhaust pipe; and the prepared water-cooling exhaust pipe has higher tensile strength, higher hardness, better graphite morphology and better graphite grade, and the amount of stable pearlites is 98% or more. The yield of castings is improved from 54% to 96% or more. The finished product is good in texture compactness, good in texture refining capability, good in surface quality, and stable and reliable in quality. Also, during the production, the method has the advantages of being small in use level of the sand and paints, small in equipment investment, small in equipment occupied area, high in production efficiency, low in manufacture cost, good in environmental protection property, wide in prospect, and applicable to production of various engine exhaust pipes with high quality demands and complex thin-wall double-layer walls.

The invention provides a melting ingredient for a piston, and the melting ingredient is mainly used for solving the problems that the pistons cast and formed from the existing melting ingredient are easy to deform and wear and have lower hardness and larger brittleness. The melting ingredient for the piston comprises the following components in percentage by weight: 2.3-3.5 of carbon, 1.7-2.2 of silicon, 0.6-0.9 of manganese, 0-0.12 of sulfur, 0-0.1 of phosphorus, 0-0.06 of chrome, 0.01-0.02 of antimony, 0.2-0.5 of copper and the balance of iron. The melting ingredient for the piston is molten, casted and formed to obtain a piston finished product; and the obtained piston finished product is not easy to deform and wear and has the advantages of high tensile strength, less brittleness, good graphite morphology and lower cost.

The invention relates to a high-strength and high-wear-resistance vanadium-titanium cast iron brake drum manufacturing technology for automobiles, specifically a method for preparing a vanadium-titanium gray cast iron brake drum. The preparation method includes the following steps: melting the original molten iron: Vanadium-titanium pig iron, scrap steel, furnace charge, recarburizer, ferrosilicon, ferromanganese, and ferrochrome are used as the charge, and the recarburizer is added to the bottom of the furnace, and the charge is smelted in an intermediate frequency induction furnace to obtain the original molten iron. After the molten iron is melted Raise the temperature and overheat to purify the molten iron, then keep it warm at 1520-1530°C; then carry out slag removal, add a slag accumulator on the surface to keep it warm, and then add a small amount of recycled material to adjust the composition of the molten iron. The invention adopts the process of adding a small amount of returned material to increase the heterogeneous core in the later stage of smelting to reduce the tendency of molten iron to be white, improve the graphitization ability of molten iron, and improve the inoculation effect; adopt the secondary inoculation treatment process of the tapping trough and the sprue cup to improve the inoculation effect , Improve graphite morphology, eliminate carbide and ferrite, increase pearlite content.