Lost Wax Investment Casting-An Ancient Art Revived
The technique of lost wax investment casting is an ancient art, stretching back thousands of years for everyday objects, jewelry, and now even metal components for industrial use. This casting process begins with preparing a mold of the desired shape, usually from metal, wood, rubber, or plastic. Wax, generallybeeswax with a low melting point, is then melted and poured into the mold. It is then allowed to cool and harden, forming a perfect replica of the desired shape.
The next step in the process involves coating the wax replica with several layers of a refractory material, such as clay or a slurry containing silica and zircon, then allowing it to dry. This process is known asinvestment and is designed to protect the wax replica from the temperatures of the molten metal and prevent it from melting away.
The wax replica is then placed into an oven and heated to a temperature slightly higher than the burning point of the wax. This causes the wax to melt away or burn out and leave a hollow cavity in the investment. Molten metal is then poured into the cavity left by the burnt-out wax, and allowed to cool and harden. When the metal has cooled, the refractory investment can be broken away, leaving a perfectly formed metal object.
This process is commonly used to create complex shapes, intricate designs, and high-precision parts that other methods like die casting simply cannot provide. Small series or a single one-off objects can be created with the same speed and efficiency as mass-produced items. This makes the process especially attractive to smaller companies, who may not need large numbers of the same item and are therefore unlikely to justify the costs associated with die casting.
The lost wax investment casting process offers excellent results in terms of both cost and quality, making it popular for countless applications. Bicycle components, golf clubs, architectural and automotive components, jewelry, and many more items have been created using this technique. It is an ancient art that is seeing a bit of a revival as people realise that it is still a remarkably effective way to create complex parts quickly and economically.
