When we talk about traditional casting methods, investment casting manufacturing process comes in our mind. It is being used by people since thousands of years to cast distinct shapes using expandable ceramic mold.
They pour molten metal into the mold and extract the casting once it gets cool. The mold is prepared by investment castings manufacturers using wax pattern – which is a disposable piece in the shape of the desired part.
The pattern is invested into ceramic slurry that hardens inside the mold.
This investment casting process is also recognized as lost wax casting process as the wax pattern is melted out of the mold after it has been developed. However, as the mold is destroyed during the process, manufacturers of investment castings are able to create complex geometrics and detailed components.
Investment casting can make use of maximum metals, some of them are aluminium alloys, bronze alloys, cast iron, magnesium alloys, stainless steel, and tool steel. This method of casting is advantageous for casting metals with extreme melting temperatures that are impossible to mold in plaster or metal.
- Also Read: Applications of Duplex Steel Castings
Parts you can cast through investment casting include complex geometry like turbine blades, firearm components, etc. Automotive, aircraft and military industries are also making some of the parts via investment or lost wax casting method.
Investment casting needs several components to carry out the casting process- metal die, wax, ceramic slurry, molten metal, furnace, and machines needed for sandblasting, grinding, or cutting. How it is performed by manufacturers? Let’s learn the steps of investment casting process-
The wax patterns are usually injection molded into a metal die and are developed as single piece. Manufacturers may use cores to form any internal feature on the pattern. They link such patterns together to a central wax gating system, to form a tree-like assembly. The gating system creates the channels through which the liquid metal flows to the cavity.
The created pattern tree is dipped inside the slurry of ceramic, coated with more coarse particles and then dried. Once it gets dried, it forms a ceramic shell around the patterns and gating system. This mold creation process is repeated until the layer of the shell gets thicken to withstand the molten metal it will encounter.
The mold is preheated inside the furnace and the molten metal is poured to the gating system of the mold from a ladle. Pouring is achieved under the gravity force.
Once the mold is filled, manufacturers allow molten metal to set and solidify into final casting shape.
Once the casting is solidified, manufacturers break the ceramic mold using water jets and separate the casting part.
Final product is then sent to finishing section where experts use grinding or sandblasting method to smooth the part.
For more details about the casting process, write to investment castings manufacturers and clear your doubts.