Eagle Alloy

Our Services

Eagle Alloy has been providing West Michigan with the highest quality custom steel casting services since 1979. As a premier shell-mold foundry, we specialize in pouring various carbon and stainless steel grades. Our expertise lies in producing top-quality shell-molded steel and stainless steel castings to fulfill all production requirements.

Services at Eagle Alloy start right at the onset of the casting process. Our sales, engineering and design teams work closely with customers each step of the way, especially on large, long-term projects. Through this collaboration, our engineers provide specialized guidance on casting and machining, ensuring parts are developed within the principles of Design for Manufacturability or DFM. This approach guarantees that components perform to the standards our customers require and optimize cost-efficiency—an exemplification of true value engineering (VE).

We go beyond providing exceptional customer service and superior products; we also focus on maximizing your investment. To achieve this, we employ various techniques, such as:

  • Identifying key factors that impact manufacturing costs.
  • Recommending the correct datum scheme to ensure proper part fit, function and accurate measurement results.
  • Explaining potentially trouble areas in the manufacturing process.
  • Tailoring the design process to specific project requirements, including:
    • Custom tooling and fixtures for efficient production, and
    • Developing models for strategic capital investment.

We believe that when customers are well-informed about the stainless steel casting process, alloys and casting methods, they can make more informed decisions during production. Our services include a broad range of value-add services including 3D solidification simulation software, an in-house X-ray, advanced quality and delivery programs, and a complete machining facility.

Below are descriptions of various aspects of our stainless steel casting process at Eagle Alloy, along with more detailed information about our services. For additional questions, please visit the Eagle Blog.

A guide to stainless steel casting

What is stainless steel casting?

Stainless steel casting is a process in which molten stainless steel alloy is poured into a prepared mold to create a part. The mold’s shape depends on the design specifications of the part, and is often formed by coating a pattern with a material that can resist the high temperatures of molten steel. After the molten alloy is poured into the mold cavity it is, allowed to cool and solidify into the final shape. The finished product is extracted and cleaned.

For more information on metalcasting processes, consult our “Introduction to Metalcasting” article.


Is stainless steel easy to cast?

Stainless steel is a versatile material in casting manufacturing, but it requires careful consideration. Stainless steel is a ferrous alloy, meaning it’s a metal whose composition contains mostly iron. Additional metals such as chromium, manganese, nickel, molybdenum and vanadium strengthen its metallic bonds and raise its melting point. Higher chromium content, in particular, makes the alloy harder to melt and cast. Consequently, stainless steel can only be used with casting processes that can withstand high temperatures, like shell molding and investment casting. The mold design must also accommodate stainless steel’s expansion when heated to prevent surface irregularities or cracking. Ensuring a sufficiently high casting temperature for complete melting without damage is crucial, as is maintaining impurity-free melts to prevent defects like porosity.

What are the benefits of cast stainless steel?

Cast stainless steel is known for its strength and corrosion resistance. Compared to most grades of carbon steel and other comparable alloys, stainless steel grades are often more ductile and tougher, making them less likely to break during operation. At Eagle Alloy, we can cast stainless steel to produce custom, intricate shapes at high volumes, optimizing investment efficiency. Other benefits to using the cast stainless steel process include:

  • High heat resistance
  • Excellent resistance to tarnishing, wear, and corrosion
  • Exceptional durability

Our Alloys

At Eagle Alloy, we pour a variety of grades of steel and aluminum alloys tailored to meet your product’s performance needs. Some of the alloys we pour include:

  • Stainless steel
  • Carbon Steel
  • Nickel Alloys

Each alloy possesses unique strengths suited for specific purposes. Depending on your part, we have the right alloy to ensure optimal performance. Some of these strengths include:

  • Structural suitability
  • High or low-temperature performance
  • Suitability for heavily walled parts

For more specific information on the alloys we pour and their characteristics, refer to our Material Specifications List.

Eagle Alloy’s casting processes

Eagle Alloy uses two types of casting methods: the shell mold process and the airset process. Both are suited for casting steel and stainless steel, but have different ideal use cases. Our team will help you to identify the most suitable casting method for your specific part requirements.

Shell mold process

The shell mold process is the industry standard for medium to high-volume commercial casting projects. For a deep dive into the process, watch our 3D video animation or read our Shell Molding Process Guide.

In the shell mold process, thermally bonded sand is applied to a pre-heated pattern, typically made of cast steel or cast iron. The “baked” mold is then lifted from the pattern in halves and glued together, using precise locating features to avoid shifting. Molten metal is then poured into the pre-made mold, with a core used if the part requires hollow cavities. The mold and core are sand-bound at high temperatures. Once heated, the molten metal is poured into the mold to form the part. Excess sand is cleaned off, and secondary processes such as heat treatment, machining and coating are applied. The shell-mold process offers tolerances of +/-.030” on dimensions 6” or less and a surface finish around 150 – 300 RMS.

Advantages: Good casting detail, excellent repeatability, very productive, less machine stock required than in greensand or no-bake processes, competitive pound-prices, very short production lead times.

Disadvantages: Tooling prices higher than some other processes.

Shell Molding Tolerances, Capabilities & Design Recommendations

Airset process

The airset or “no-bake” casting process is similar to the shell mold process, but with a key difference: it uses resin as a fast-curing adhesive during casting instead of heat. In airset casting, the chemically bonded sand sets at normal temperatures, hence the nickname “no-bake” casting. This process can utilize finer sand that wouldn’t bond well without a chemical additive, ensuring a strong mold. Airset casting also yields consistent parts with minimal surface defects, resulting in aesthetically appealing products. As a result, manufacturers often save on machine finishing costs, making this process cost-effective. The airset process offers tolerances of +/-.063” on dimensions 6” or less and a surface finish around 250 – 560 RMS. Read our blog post on Getting started with Airset casting for more information about this process.

Advantages: Good casting detail, inexpensive tooling, can use a simplified sand mix, uniform hardness throughout the mold, molds are extremely strong.

Disadvantages: Limited bench life for the chemically bonded sand mixture, not ideal for large volumes due to time required for mold to set

Airset Casting Tolerances, Capabilities & Design Recommendations

When it comes to choosing the right steel casting process, every manufacturer must decide on the right process to use. Casting methods like shell molding, greensand casting, investment casting and airset casting all have their own sets of benefits and drawbacks. The optimal choice depends on the factors like production volume, part size, and the specific requirements for dimensional accuracy, surface finish and material properties.

You can trust that at Eagle Alloy, our team of engineers will help you determine what casting method will work best for your part before we begin production.

 

Steel alloy casting and 3D printers: from prototype to product

Our engineering team offers end-to-end support in developing prototype parts, starting from the initial concept to production casting. Leveraging 3D-printed molds and cores, design adjustments can be made “on the fly”. This proactive approach allows us to identify and modify casting design flaws upfront, mitigating the need for costly tooling alterations later on.

Eagle Alloy collaborates with various pattern and machine shops to outsource 3D printing of sand cores and molds. We do this to minimize manufacturing costs due to potential flaws in the casting design. We are then able to pour, process and heat treat the castings to meet your specifications.

Explore our 3D-sand printing slideshow and dive deeper into our utilization of 3D printers in production through this video, courtesy of ExOne (1).

Project management

At the Eagle Group, our sales, quality, engineering and production teams collaborate seamlessly to support you in designing, producing and sustaining a product that is tailored to your specific application. From steel and stainless steel casting to heat treating, machining, painting, and even specialized processes like passivation, induction hardening and flame hardening, we cover all aspects of production with standard practices. It’s all in a day’s work. We can also help you to identify and minimize cost drivers in your project and then develop and deliver that project within some of the shortest and most consistent lead times in the industry. Choose Eagle Alloy to assist in managing your project, and benefit from exceptional project management throughout the product lifecycle.

Engineering

Our dedicated team of engineers ensures high-value parts that consistently exceed expectations. Through our Advanced Quality Planning (AQP) process, we evaluate all metallurgical and dimensional aspects of your product to optimize production efficiency. For modifications to your part during production, we use MAGMA solidification software and 3D CAD propose design changes as needed, coordinating prototypes with final products to ensure the casting will perform correctly. Our AQP process extends from sampling to MRB review, approval and evaluation of the first production run.

Metrology

We use a combination of traditional and cutting-edge measuring techniques to guarantee precise dimensions and measurements for your product, accurate down to the millimeter. Our methods include utilizing Coordinate Measurement Machines (CMMs) and advanced laser scanning technology for inspecting both samples and production parts. We also use specially designed go/no-go gauges to confirm dimensional requirements on critical features of the production parts and employ a high-resolution Creaform Exascan 3-dimensional laser scanner to achieve accuracy within approximately .0008 inches. Lastly, by utilizing Geomagic Verify alongside the scan data, we can inspect critical features and directly compare all casting features to the original solid model design. This process allows us to easily identify any inconsistencies in the final product that could negatively impact its application, and we can share scan files with our sister machine shop and customers for further analysis.

If you choose Eagle Alloy for your casting needs, you can expect the highest quality each step of the way. From prototype to production, our team of professionals are dedicated to making your part the best that it can be. For any further questions, please visit our Blog or contact one of our representatives.

References:

(1) 3D Printing Systems, ExOne
https://www.exone.com/en-US/3D-printing-systems