Investment casting is a manufacturing method that is used to create complex and detailed industrial parts and shapes. This is accomplished by starting with a wax model of a part that is then turned into a mold. The mold, in turn, is filled with molten metal.
The process of investment casting starts with the creation of a wax model that is then attached to a sprue. Hundreds of wax model molds can be fixed to the same sprue at one time, this is called a tree. The tree is dipped into a slurry compound several times before it is sprinkled with an abrasive material resembling sand. Once the investment around the wax is thick enough, it is placed in an industrial oven where temperatures exceed 1000 degrees Fahrenheit. The wax might melt and drip during this time, but it keeps its shape. Whatever metal that is being used is heated until it is in liquid form and then poured into the hollow mold. Once the metal has cooled to the point that it is no longer red hot, the shell around it is removed and the cast metal parts are cut off of the sprue. Read More…
Although many different metals can be used in an investment casting, aluminum is by far the most common. Stainless steel and copper are also popular choices. Stainless steel is used primarily for applications where the casting will be exposed to harsh material or elements because of its anti-corrosive properties. Because copper castings are light and strong, they are often used for pipe fittings, jewelry, mixing equipment and more.
Other casting materials include steel and titanium. Steel is stronger than iron, so steel investment castings are usually used to create parts that must withstand heavy loads or impacts. Titanium castings are very light while still being very strong, so they are often applied to use in things like turbochargers, industrial tools and a whole host of aerospace and defense applications components.
Therefore, it is very important to identify the necessary characteristics of the final casting when deciding on the type of material to use.
Investment castings are used for manufacturing in major industries like aerospace, chemical, defense, electrical components, railroad, marine, electronic, textile and more.
Investment casting allows modern manufacturers to create castings with the exact same results every time. While the investment is being mixed, contaminants like dust particles are removed by fans and blowers to maintain purity. A vacuum can be integrated into the system to prevent air bubbles from forming. The industrial ovens that are used for investment casting have very precise temperature controls to create the right burnout. Other heating equipment makes it very easy to melt alloys to the right temperature for a molten flow. Chemical-enhancing formulas can be added along the way to improve the material qualities of the casting for added durability.