Types of aluminum molds

There are many types of aluminum molds for casting molten aluminum into different shapes and forms. Some molds are temporary, while others are permanent and can be reused. In addition to aluminum, these same types of molds are used in many different metals and alloys.

Sand mold

The oldest mold for aluminum castings is the one used since the Egyptians. These types of molds are made when creating cavities in the sand contained in boxes or "flasks". Usually, the original "pattern" is made of wood, metal or other solid materials. There is also a core in the sand cavity, which forms the center of the casting. Among the different aluminum molds, the mold is especially used for engine blocks, engine manifolds and other large and heavy castings.

Ceramic mould

Another casting mold used with aluminum and other molten metals is a ceramic mold. The most commonly used in the investment casting process is that the ceramic mold is made around plastic or wax, and the plastic or wax is melted when it is fired when the mold is formed. After the wax is "lost," the mold is ready to receive molten metal. This type of casting process is also called "precision casting" because it can be used to create precise castings.

Permanent mold

The permanent type of aluminum mold is made of metals such as steel and iron. The molten aluminum is forced into the permanent mold cavity under the influence of gravity or vacuum. One of the advantages of these molds is that the molds are permanent. Unlike sand casting molds, the latter usually destroy the casting when it is taken out after cooling. It is also cheaper when used for a large number of castings.

Die casting mould

Die casting molds use steel dies or molds to produce many of the same castings. Like aluminum, molten metal is pressed into these types of aluminum molds under high pressure. This is a universal process that can produce a large number of small and medium castings.

Shell mould

The shell mold is a sand casting mold that uses resin to bond sand to a thin shell 10 to 20 mm thick. Although the use of these types of molds for aluminum castings produces better surface finishes and more precise dimensions, this process is certainly more expensive.

Gypsum mould

Gypsum molds are made by pouring gypsum slurry around wax or other types of consumable materials (such as foam). When baking the plaster mold, the pattern will melt, so that the pattern is perfectly presented. The molten metal is then poured into the cavity of the gypsum mold. This is another form of "lost wax casting".

Graphite casting mold

Graphite molds and cores are commonly used in aluminum centrifugal casting. This process presses the metal into the mold and uses rapid cooling to produce high-quality castings that cannot be achieved by other methods.

These are the seven most commonly used aluminum molds for the production of aluminum castings. Each mold is used to produce specific quality castings and has different types of casting properties.