The investment casting process is capable of producing parts to exacting specifications using a variety of ferrous and non-ferrous alloys. But choosing the right investment casting material for your application is important. The right material can help you achieve the functionality you need, save on material costs, eliminate unwanted casting defects, and limit the need for secondary machining after casting is complete.
Types of Investment Casting Materials
There are many materials suitable for investment casting, and there are the following types to choose from.
Stainless Steel
The biggest advantage of stainless steel is its excellent corrosion resistance. Stainless steel investment castings have a built-in layer of chromium oxide for superior durability compared to many other materials. These corrosion-resistant properties make stainless steel castings ideal for military, plumbing, medical, and food industry applications.
Low Alloy Steel
Low alloy steels are among the most frequently used steels in the mechanical world due to their affordability and beneficial mechanical properties. Low Alloy Steels are used for their strength, toughness, and resistance to effects such as corrosion. This is due to the addition of elements such as Nickel and Chromium amongst others.
Aluminum Alloy
Aluminum alloy is the most used material in investment casting. Known for its high strength-to-weight ratio, aluminum can be heat treated to achieve higher strength, ductility, corrosion resistance, and workability.
We use 300 series aluminum in many investment casting applications. The advantage of 300 series aluminum is its high tensile strength and ductility for pressure applications. Industries that use it most often include aerospace, avionics, electronics, and the military.
Carbon Steel
Carbon steel is the most commonly used steel in the world. It is the most popular choice when using investment casting because of its high structural integrity, especially when heat treated. The strength, ductility and properties of carbon steel in industrial applications can be improved by heat treatment. Its ferromagnetic properties allow carbon steel to be used in motors and appliances. It is safe, durable, and has high structural integrity, making it one of the most commonly used alloys in the world.
Super Alloy
Super alloys based in nickel and cobalt have common uses in the aerospace, energy, medical, chemical, and marine industries. Nickel-based alloys are stronger at high temperatures and cobalt-based alloys have superior corrosion, oxidation, and wear resistance over their nickel-based counterparts. Super alloys increasingly replace sheet metal because they provide high rigidity and superior service characteristics while remaining a cost-effective option.
Copper Alloy
Many part types can be investment cast from copper-based alloys. More common types of copper-based alloys include bronze and brass. Copper-based alloys are corrosion-resistant and feature low rates of wear. The strongest copper alloy is beryllium-copper, which has similar properties to high-strength alloy steels but with a higher corrosion resistance over longer periods.
They are frequently used in applications such as ship or pump propellers, electrical components, and plumbing components.
Cast Iron
Iron castings, which often include gray iron and ductile iron, are known for their high accuracy and an affordable price tag. Ductile iron has high strength, heat resistance, and toughness, but it has a more complex production process than other steels. This leads to a higher production cost than cast steel.
Cast iron usually refers to gray iron and ductile iron. Such kind of investment casting material can be used to produce iron castings with carbon content higher than 2%.
Common gray iron grades: HT150, HT200, HT250, HT300, HT350.
Common ductile iron grades: QT400-15, QT400-18, QT450-10, QT500-7, QT600-9.
The Best Casting Material for Your Project
Besser is a professional investment casting factory, we use a strictly controlled investment casting process to provide high performance high quality products. We have a wide range of premium casting materials to help you achieve the functionality your design requires.
For more information on material selection, or learn about our investment casting services. Please contact us and let us know how we can meet your project needs.
Recommended reading about investment casting