Investment Casting

    Investment casting, also known as lost-wax casting, is one of the key methods for producing complex metal parts. In this process, a ceramic mold is created by the layering ceramic slurry over expendable patterns. These patterns are subsequently removed from the mold through heating or burning, leaving behind a hollow ceramic mold ready for metal pouring.

    Investment Casting Process

    Pattern Production
    The conventional method for creating expendable patterns involves injecting wax into a metal die.
    In addition to traditional methods, Badr Engineering System Company also utilizes additive manufacturing technologies to produce these patterns.

    Ceramic Cores
    To create internal geometries—such as air-cooling channels in gas turbine blades—ceramic core technology is employed. In this method, the ceramic core is first placed into the metal mold, and wax is then injected around it to form the external shape of the part. 

    Wax Assembly (Wax Tree)
    Wax patterns, feeders, runners, and other wax components are assembled based on a gating system to form the wax tree.

    Ceramic Shell Building
    Ceramic shell building is one of the most critical and precise steps in the investment casting process. In this phase, the wax assembly is dipped into a ceramic slurry and then coated with ceramic stucco. After drying, the process is repeated multiple times until the desired shell thickness is achieved.

    Dewaxing
    To create a hollow mold, the wax must be completely removed. Dewaxing is carried out prior to metal pouring using autoclave or flash fire techniques to melt and extract the wax from the ceramic shell.

    Firing and Preheating
    After dewaxing, the shells are fired to achieve sufficient strength, and any remaining wax residues are completely eliminated during this stage.

    Inspection and Preparation
    The fired molds undergo quality control, insulation wrapping, and filter placement in preparation for casting.

    Pouring (Metal Casting)
    The ceramic molds are preheated in dedicated furnaces and then transferred to vacuum induction furnaces (VIM) for metal pouring.
    Badr Engineering  System Company is capable of casting nickel, cobalt, and iron-based alloys and superalloys using VIM furnaces with capacities ranging from 5 to 200 kilograms.

    Part Removal
    Once the poured molds have cooled to room temperature, the ceramic shell is removed using pneumatic hammers. The metal components are then separated from the gating system using cutting equipment.