Why Aluminum Investment Casting?
It’s no surprise that aluminum isn’t excluded from the investment casting party. Aluminum features a wide range of physical properties that make it a favorable candidate for investment casting. The primary reasons for aluminum’s popularity are its high strength-to-weight ratio and its corrosion resistance. Aluminum is a very strong metal considering its weight. Certain aluminum alloys are attractive alternatives to ferrous metals because they can provide comparable strength without the negative quality of high corrosion susceptibility. Aluminum is also a good candidate for a wide variety of metal working and metal working processes, and investment casting is no exception.
The investment casting process involves the creation of a wax pattern by an engineer. This is true regardless of which kind of metal is going to be cast during the process. After the pattern design phase is finished, the pattern must be layered with a ceramic shell. There is some variability to this process, and the process will be performed differently depending on the needs of the casting process. Once the shell has been fully formed, the wax around which the shell formed is melted and lost (this is why investment casting is sometimes also called “lost wax casting”), and the shell is ready to be used for the casting process.
At this point, the aluminum is melted and invested into the shell. Aluminum’s melting point is around 660°C, which is much lower than the 1370°C at which some varieties of steel melt. This means that aluminum investment casting can require lower amounts of energy for the melting process. After the aluminum is invested into the shell, it takes the shell’s shape. It eventually cools and hardens, and then when the shell is destroyed, a newly investment cast aluminum part emerges. This part will be characterized by its strength, light weight and corrosion resistance.