The Federal Group provides high-quality investment casting services for businesses in just about any industry. We have worked with a wide variety of companies over the past 40 years, delivering quality parts for a wide range of products.
What Is Investment Casting?
Investment casting is one of the oldest techniques for metal forming. This coating process involves the creation of a pattern or prototype of your desired part.
The master pattern can be made using several different methods including 3D printing or wood carving. After injecting wax into the master die, the wax cools to create an exact replica of the original pattern.
The wax pattern is typically coated in a ceramic material. This is the investment material. After the ceramic material hardens, the pattern is heated to a high temperature, allowing the wax to melt and drain from the ceramic shell.
Along with a ceramic slurry, brass, aluminum, or stainless steel alloys may be used. After draining the melted wax from the investment mold, molten metal is poured into the empty mold. The metal hardens and the investment material is broken, revealing the finished part.
As the wax model and ceramic mold are destroyed to remove the finished part, the process requires a die made from a master pattern. This increases the lead time for the project. However, some of the benefits of investment casting help offset the extended time frame.
Investment Casting Advantages & Disadvantages
Every process comes with pros and cons. While investment casting is useful for creating complex parts, it also has a few drawbacks. The advantages of the investment casting process include:
- Greater accuracy
- Superb surface finish
- No flashing or parting lines
- Compatibility with almost any metal
- Ability to produce intricate parts
Investment casting delivers superior accuracy, making it a precision casting solution for producing intricate parts. We can achieve net shape or near-net shape parts.
Our investment casting foundry is equipped with the most modern equipment, including a quality gating system that reduces casting defects. This process also results in a smoother finish. The mold eliminates flashing or parting lines in the finished product.
These benefits reduce the need for surface finishing and shorten the overall production timeline.
The ability to produce parts with finer details makes this a popular choice for products that require greater precision. However, these advantages also come with the following potential disadvantages:
- It may require a longer production cycle.
- Investment casting is often more expensive.
- Casting parts that require cores is difficult.
The initial steps needed to produce the dies and molds may extend the overall production timetable. The typical timeframe from the creation of a fresh wax pattern to the completed part is seven days.
The creation and drying of the ceramic mold are the most time-consuming parts of the process. It also takes longer to change the design as new molds may need to be created.
The overall cost of investment casting may be higher compared to our other casting services. The higher cost comes from the need for additional material, labor, and equipment to create the ceramic molds. However, the relative cost tends to decrease with high-volume production runs.
While investment casting allows us to create complex components, adding a core or cavity to the part increases the complexity of the project. Investment casting is a specialized solution for specific projects. It is often used for parts that require greater precision.
For example, this process is frequently used for the fabrication of small parts for cooling systems, firearms, and aerospace equipment.
Investment Casting vs. Sand Casting: Which Should You Choose?
Investment casting is not the only casting service that we provide. We also offer sand casting, rapid prototype casting, centrifugal casting, lost foam casting, permanent mold casting, and die casting.
Investment casting is commonly used to produce parts that require extreme precision. This casting process allows for thinner walls and complex internal cavities.
Compared to other casting techniques, investment casting provides finer details and superior surface finishes.
For example, sand casting involves the use of a sand and clay mixture to create a mold around a pattern of the final product. The mixture is more porous compared to the wax patterns used for investment casting, limiting the ability to create intricate parts. Along with a smooth finish, investment casting parts can be made from a variety of materials.
Why Choose Our Investment Casting Services?
The Federal Group prides itself on its experience and commitment to quality. At TFG, we also ensure that every customer receives the following benefits with our specific processes:
- Specialized shell making equipment
- Reliable quality assurance
- Short runs or high-volume production
We use state-of-the-art wax processing equipment. Our semi-automatic wax injection machine allows us to fabricate wax patterns more quickly and reduce the timeframe to completion.
Our dewaxing machine melts the pattern quickly without cracking the investment. We employ specialized equipment to pour the molten metal without creating air bubbles, minimizing the risk of defects. This is followed by a thorough quality assurance process.
We also work with a wide range of materials including super duplex stainless steel, duplex stainless steel, aluminum, brass, copper, magnesium, and grey, ductile, or white iron.
The Federal Group’s Capabilities
The Federal Group has wax processing equipment that recycles used wax. Our shell making equipment and a semi-automatic wax injection machine allow for rapid pattern fabrication. Our dewaxing machine thoroughly and quickly melts the pattern so the initial expansion of the heated wax doesn’t crack the investment. When pouring the molten metal into the mould we can use our specialized equipment to reduce product defects from the presence of air bubbles:
- Horizontal Vacuum Precision Furnace
- Vertical Vacuum Precision Furnace
- High-pressure Gas Quenching Vacuum Furnace
We can work with the following materials and more:
- Stainless Steel, Duplex 2507: A super duplex stainless steel with 25% chromium, 4% molybdenum, and 7% nickel alloy. Designed for applications which require exceptional strength and corrosion resistance.
- Stainless Steel, Duplex 2205: A two-phase, ferritic, austenitic 22% chromium, 3% molybdenum, 5 to 6% nickel alloy. It is the most widely used duplex stainless steel grade and is characterized by high yield strengths. It has good fatigue strength and demonstrates outstanding resistance to stress corrosion cracking, crevice, pitting, erosion, and general corrosion in severe environments.
- Grey, Ductile, and White Iron: Used for a variety of purposes for ease of machinability, ductility, or compressive strength
- Aluminum: Investment casting of aluminum enables the casting of complex-geometry parts with shorter lead times, greater alloy flexibility, tighter dimensional tolerances and better surface finishes. The result requires less machining and processing.
- Brass/Bronze: It offers excellent machinability, corrosion resistance, and aesthetics.
The end result of investment casting yields highly intricate and accurate parts with tight tolerances to be used in aerospace, marine, and automobile manufacturing and beyond.