Comparison of Precision Mold Casting Methods
Several precision casting methods each have their own advantages and limitations.
Several precision casting methods each have their own advantages and limitations. For example, investment casting can produce more complex castings, but it is not suitable for larger castings; The applicability of ceramic mold casting for complex parts is not as good as other methods; The coating transfer method results in unstable casting quality due to the influence of coatings and production processes; Lost foam casting has a large amount of gas generation, low pattern strength, and poor mechanical properties of the castings. Table 1 compares the dimensional accuracy and surface roughness of several precision casting methods.
However, there is currently a major difficulty in the production of high-precision molds. The accuracy of the pattern will directly affect the accuracy of the mold, and currently the material used for the pattern is generally wood or metal. Wooden patterns can expand and become unstable in size when exposed to moisture and heat, while metal patterns have disadvantages such as manufacturing difficulties, high costs, and long production cycles, making them not ideal material for patterns. If the resin prototype manufactured by rapid prototyping technology is used as a casting pattern, it is very ideal. The dimensional accuracy of the RP prototype reaches ± 0.1mm, and the surface roughness (Ra) of the RP prototype using SLA technology is 0.6 on the upper surface, respectively μ m. Bevel (45 °) 6.9 μ m. Vertical plane 4.6 μ m. Therefore, the combination of rapid prototyping technology and precision casting technology is an effective method for manufacturing molds, especially for molds with complex shapes or cavities, its advantages are more obvious.