Investment casting is a type of metal casting process in which a wax pattern is used as a printing medium. Wax patterns are created from master dies using metal or other materials. Investment casting is another type of casting that creates products with precise dimensions.
Stages of Making Investment Casting Mold
- Pattern making with wax. The master die is used to mold the molten wax pattern by pouring or injecting it into the master die. Remove the wax pattern from the master die once the wax has solidified.
- After the wax pattern has been finished molding with the parent mold, it is attached to a wax gating system (pour channel).
- Runners (flow channels) and sprues (inlets) form clusters when the gating system is included (pattern trees).
- The pattern tree is then immersed in a ceramic slurry solution for 4 hours at a temperature of about 23 °C.
- After being settled, the pattern tree is dipped back into the ceramic slurry, and when lifted, it is sprinkled with sand grains and dried as in the previous stage.
- The number of coatings applied varies according to the requirements and stage of the trials.
- The pattern tree that has been coated to the final layer is then dewaxed (wax removed) by heating at a temperature of about 120 °C.
- When the dewaxing process begins, the pattern is inverted so that the wax liquid can exit the sprue.
- Sintering at a temperature of around 1000 °C is the final stage in the production of mold investment casting.
- The pouring process begins after the sintering stage is completed (pouring metal liquid into the mold). Pouring takes place in a hot mold after it has been placed in the sintering furnace.
So those are the steps in the process of creating investment casting molds up to the pouring process.
Following that, we will discuss its advantages and disadvantages.
The advantages and disadvantages of investment casting
Advantages:
- Produces a cast product surface that is smooth and free of parting lines.
- Can create casting products with a high level of complexity that other casting methods cannot.
- Dimensional accuracy is excellent, with a tolerance of about 0.076 mm.
- Casting products do not necessitate complex machining processes (for certain cast products).
- Candles can be recycled to create new patterns, saving both time and money.
Disadvantages:
- Because the stages of the process are relatively long, they necessitate a significant amount of effort, time, and money.
- Only small cast objects are permitted.
- Applying to products that require cavities (using cores) is difficult.