Full-mold casting refers to the casting method which uses polystyrene foamed plastic pattern instead of common pattern and pours metal liquid into the mold without removing the pattern after making the pattern. Under the action of metal liquid, the plastic pattern burns, gasifies and disappears, metal liquid replaces the space occupied by the original plastic pattern and obtains the required casting after cooling and solidification.Solid casting is also known as cavity-free molding.
1. Making Method
Styrofoam moulding allows pouring without moulding.During pouring, the foam is heated, burned and vaporized, and its position is filled with liquid metal. After cooling, the foam becomes a casting with the same pattern.
(1) Because of the foam plastic pattern which is vaporized when meeting the metal liquid, no moulding, no parting surface and no core are required, there is no flying edge burr. The dimension accuracy and surface roughness of the casting are close to that of investment casting, but the dimension can be larger than that of investment casting; (2) The pattern of various complex castings can be bonded by foam plastic pattern, forming into a whole, reducing the processing and assembling time.The cost of castings can be reduced by 10%~30%, which also provides sufficient freedom for the design of castings structure; (3) The production process of castings is simplified, the production cycle is shortened, and the molding efficiency is 2~5 times higher than that of.
The pattern of full-mold casting can only be used once, and the density and strength of foam plastics are small and the pattern is easily deformed, which affects the dimensional accuracy of the casting.Gases produced by the pattern during casting pollute the environment.
Full-mold casting is mainly used for batch and single-part production of complex castings such as difficult to lift.