Composite cold iron for iron castings and production method thereof

Abstract

The invention relates to efficient composite cold iron for iron castings and a production method thereof. The composite cold iron comprises a main body; the main body comprises a coating layer and a gray iron layer; the coating layer is prepared by adopting common carbon steel; the gray iron layer is prepared by adopting gray iron; the coating layer is of a cavity structure; the gray iron layer is matched with the coating layer; the gray iron layer is cast in a cavity of the coating layer; and a boss positioning hole is formed in the side wall of the coating layer. The composite cold iron further comprises a boss for preventing slippage; and the shape and the size of the boss positioning hole are matched with that of a projection part of the boss. The production of positioning grooves by steel cold iron in the prior art is high in cost; the cold iron slips due to improper production to cause the casting waste; the steel cold iron is high in material cost; and in order to solve the defects in the prior art, the invention provides the composite cold iron for the iron castings and the production method thereof. The cold iron for the iron castings has the advantages of good surface quality, long service life, simple production, low cost and high cooling efficiency.

Description

technical field [0001] The invention relates to the technical field of casting, in particular to a composite chill for iron castings and a production method thereof. Background technique [0002] Casting refers to the processing method of melting solid metal into liquid and pouring it into a mold of a specific shape, and waiting for it to solidify and form. In order to obtain the structural shape of the part, other easy-to-form materials are used to make the structural shape of the part in advance, and then in the The sand core is put into the sand mold, so a cavity with the same size as the part structure is formed in the sand mold. Ductile iron and steel castings have a large tendency to shrink and porosity. Generally, chilled iron and risers are needed to improve the filling and cooling process of castings and reduce shrinkage and shrinkage cavities. In order to make the cold iron achieve the expected ideal effect, its placement must be accurate. [0003] The cold iron ...

AI Technical Summary

Problems solved by technology

[0003] The cold iron made of gray cast iron has a short service life, often has pores and scales, which can easily lead to pore defects in castings; low toughness, severe cracking under alternating thermal stress; poor wear resistance, high volume loss rate, storage The thermal conductivity decreases rapidly, and the reuse rate is low

The cooling iron made of ductile iron, because of its smelting cost higher than that of gray iron material, and its solidification characteristics, is not conducive to the guarantee of its compactness, which directly leads to the decrease of the thermal conductivity of the cold iron

At the same time, the high carbon content of the cast iron chill iron will cause carbon deposition on the surface material during the repeated use of the chill iron, requiring a large number of surface reduction treatments, which will affect its service life

[0004] In the prior art, cast steel materials are used to manufacture cold irons. Since the thermal conductivity and specific heat capacity of cast steel materials are lower than those of cast iron materials, the lack of heat capacity sometimes causes castings to shrink and loosen; the manufacture of steel cold irons requires cutting and manufacturing positioning grooves, which is costly. Improper manufacturing can easily lead to cold iron slipping and casting scrap; at the same time, the material cost of steel cold iron is high

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