Lost Foam Casting



The pattern is made through the use of polystyrene foam. If the cast is to be made on the basis of a simple geometrical form, then the use of a hot wire foam cutter can be done. In case the volume of casting is large, then a mass production usage pattern is sued which is similar to the injection molding technique. The foam cluster done for the casting is coated with ceramic material via the use of brushing, dipping, flow casting and spraying. This form of coating is known as the refractory coating technique. After this coating dries, then the cast is put into a container and baked up on a vibration table with unbounded sand. The system of automatic pouring is significant in the Lost Foam Casting (LFC) because the pouring process is most critical in this form of casting technique (Youtube.com, 2013). The common metals that are used for casting in the Lost Foam Casting (LFC) are cast irons, nickel alloys, aluminum alloys, copper alloys, stainless steels and steels. The size of the casting ranges from 0.5 kg to hundreds of tons. The minimum thickness of the walls of the casts is 2.5 mm. There is no upper limit for the thickness of these types of castings. The linear tolerance of these casting is 0.005 mm/mm and the general surface finish ranges from 25 to 23 mm in RMS. There are different types of LFC employed in the arena of engineering and construction (Figure 3). There are many industrial applications of the Lost Foam Casting (LFC) technique. This casting process is commonly used in small scale and large scale engineering and manufacturing of products.