DIE CASTING AND LOST WAX CASTING
The two technologies belong to precision casting, which is quite different from each other. Die-casting is to pour the molten metal liquid into the steel mold on the die-casting machine, and then extruded and formed by the die-casting machine. The process is relatively simple and suitable for small non-ferrous metal pieces with low melting point.
In a nutshell, wax loss casting is to make the wax mold first, then make the shell on the wax mold. Then melt the wax mold. And finally pour the metal liquid into the empty shell after the wax mold melt. Then wait for the metal solidify and form. This complex process is suitable for small and medium sized castings of various alloys.
So, what’s the difference between die casting and lost wax casting?
1. Cost of production:
- Die casting: The biggest disadvantage of die casting is its high cost. Die casting machines and moulds and mould-related components are more expensive than other casting methods. Therefore, it is economical to produce large quantities of products when making die castings.
- Lost wax casting: The input of lost wax casting is small. And the whole process can be replaced by manual or automatic equipment. However, compared with die casting, the cost of lost wax casting is 4-6 times lower even if a full set of automatic equipment is used.
2. Different application range:
- Die casting: This process is only suitable for metals with high fluidity. And the casting quality must be between 30g and 10kg.
- Lost wax casting: The production of precision casting by loss-wax method can not only achieve mass production and ensure the consistency of casting, but also avoid the stress concentration of residual tool pattern after machining.
3. Advantages and disadvantages:
- Die casting: Because of the huge input cost, it is economical to produce in large quantities. In normal die casting, the last batch of castings is always porous. Therefore, no heat treatment or welding can be carried out. Because the gas in the gap will expand under the action of heat, resulting in internal micro defects and peeling of the surface. Die – casting parts usually have sand holes, burr, later processing is relatively complex.
- Lost wax casting: Due to the high dimensional precision and surface finish of lost wax casting, the machining work can be reduced. Only a little machining allowance can be left in the parts with high requirements, and even some castings can be used without mechanical processing. The investment mold precision casting method can save a lot of machine tools and processing hours, and greatly save metal raw materials.