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17-4 Stainless Steel Castings, Aerospace Industry, Cargo System Component
Material 17-4: Stainless Steel Castings, Cargo System Component, Aerospace
316 Stainless Steel Castings, Electrical Industry
Material 316: Stainless Steel Alloy Castings, Electrical
American Metal Testing

Stainless Steel Investment Castings

Stainless steel investment casting, also referred to as precision casting or lost wax casting, is a manufacturing process used to create complex metal parts in a wide range of shapes and sizes. It involves pouring molten stainless steel into a ceramic shell or mold, which is produced by coating a wax pattern with a ceramic material.

Aero Metals Inc. has extensive experience producing high-volume stainless steel investment castings for a broad range of applications spanning various industries, including aerospace, marine, military, and more. Check out our featured cast parts gallery for prime examples of our stainless steel casting work.

What is Stainless Steel Investment Casting?

After the initial pour and once the ceramic material has solidified around the wax pattern, the wax is melted away, leaving a cavity in the ceramic shell. The molten stainless steel is then poured into this cavity, filling the mold and taking on the shape of the wax pattern. After the metal has cooled and solidified, the ceramic shell is removed, and the finished stainless steel part is cleaned, polished, and inspected for quality.

What are the Advantages of Stainless Steel Investment Casting?

Investment casting is known for producing high-precision parts with excellent surface finish. It is a good choice for applications where precision and aesthetics are essential, such as in the medical, aerospace, and automotive industries. Additional stainless steel benefits include:

  • Corrosion resistance
  • Impact resistance & strength
  • Enhanced aesthetic value
  • Cost-effective
  • Ultra-hygienic
  • Heat resistant
  • Precision tolerances

Stainless Steel Investment Casting Material Composition

Stainless steel has a minimum chromium content of 10.5%, making it more resistant to corrosive liquid environments and oxidation. However, this is not absolute. Stainless steel investment castings are “corrosion-resistant” when used in fluid environments and vapors below 1200°F (650°C) and “heat-resistant” when used above this temperature.

Stainless Steel Investment Casting Base Alloy Elements

The base alloy elements of any nickel-base or stainless steel casting are chromium, nickel, and molybdenum (or “moly”). These three components will determine the casting’s grain structure and mechanical prosperities and will be instrumental in the casting’s ability to combat heat and/or corrosion.

Differences Between Wrought & Cast Stainless Steel

The differences between wrought and cast versions of stainless steel are due to the material’s chemical compositions and micro-grain structure, which is affected by how the material is produced, cast, or extruded. These factors must be considered when choosing an alloy for your stainless steel investment casting metal project.

Precision Casting Stainless Steel Alloy Options

Aero Metal’s stainless steel investment castings are available in several series grades, including 300, 400, 14-4 PH, 15-5 PH, 17-4 PH, and 2205.

Austenitic Stainless Steels Grades (300 Series)

300 Series austenitic stainless steels are a set of iron-based chromium-nickel alloys. The specific alloy ideal for your application depends on required corrosion resistance, formability, wear, strength, temperature resistance, cost and additional factors. 

300 Series Stainless Steel (ANSI)

Steel Grade Industry Applications
  • 303 (CF165)
  • 304 (CF8)
  • 304L (CF3)
  • 309 (CH20)
  • 310 (CK20)
  • 316 (CF8M)
  • 316L (CF3M)

 Learn more about Aero Metal's 300 Series Stainless Steel Casting Alloys.

Ferritic & Martensitic Stainless Steel Grades (400 Series)

400 series stainless steel is a stainless steel alloy similar to 300 stainless steel. The main difference between these alloys and their associated grades is their chemical makeup and components. 400 SS includes both ferritic and martensitic steels. The best alloy for your application depends on the required corrosion resistance, formability, wear, strength, temperature resistance, cost, and additional factors.

400 Series Stainless Steel (ANSI)

Steel Grade Industry Applications
  • 410 (CA15)
  • Automotive
  • Machine tool
  • Food and Dairy
  • Petrochemical
  • Firearms
  • 416 (IC 416)
  • 420 (CA40)
  • 431 (IC 431)
  • 440A (IC 440A)
  • 440C (IC 440C)
 
 

Precipitation Hardening (PH) (Martensitic Stainless Steel Grades)

Martensitic steel is a variation of stainless steel known for its high strength, hardness, and wear resistance. Martensitic stainless steel contains 10.5-18% chromium, which increases its corrosion resistance compared to other stainless steel alloys, including the 300 Series and 400 Series.

14-4 PH Series

Alloy Grade Industry Applications
  • AMS5340
  • Military
  • Medical
  • Machine tool
  • Hand Tools
  • Aerospace
 
 

15-5 PH Series

Steel Grade Industry Applications
  • ASTM A 747 CB 7Cu-2
  • Military
  • Medical
  • Machine tool
  • Hand Tools
  • Aerospace
  • AMS 5346
  • ASM 5347
  • ASM 5356
  • AMS 5357
  • AMS 5400

 

17-4 PH Series

Steel Grade Industry Applications
  • ASTM A 747 CB 7Cu-1
  • Military
  • Medical
  • Machine tool
  • Hand Tools
  • Aerospace
  • AMS 5342/5344
  • ASM 5343
  • ASM 5355
  • MIL-S-81591 IC -17-4

Learn more about Aero Metal's Martensitic Stainless Steel Alloys

Austenitic and Ferritic (Duplex Stainless Steel Grades)

Austenitic and ferritic stainless steels are highly coveted for their enhanced strength, durability, and corrosion resistance. Austenitic stainless steel contains at least 10.5 percent and 8 to 12 percent nickel, nitrogen, carbon, and many other elements in solution. Chromium gives the steel its high corrosion resistance, while nitrogen acts as a stiffening agent. 

2205 Series

Steel Grade Industry Applications
  • X2CrNiMoN22-5-3
  • Chemical processing & storage
  • Oil & gas exploration
  • Cargo tanks
  • Food & dairy
  • Marine Accessories

Learn more about Aero Metal's Austenitic Steel Alloys

Precision Casting Custom Pour Capabilities

At Aero Metals, we can custom pour any “air melted” stainless steel alloy to fit your stainless steel investment casting project requirements. If you don’t see your alloy of choice listed above, visit our Investment Casting Alloys page for more material options.

Industries that Utilize Stainless Steel Investment Castings

Premium stainless steel investment castings provide increased corrosion resistance, enhanced surface finishes, and improved detailing. Industries that commonly use stainless steel investment castings include:

  • Aerospace
  • Automotive
  • Food Processing
  • Desalination Plants
  • Pump Manufacturers
  • Machinery Producers
  • Medical
  • Mining
  • Petrochemical
  • Agriculture
  • Energy

Contact Aero Metals for your Stainless Steel Casting Project Today

Using our on-site spectrometer, Aero Metals can help you find the right alloy to fit your stainless steel casting requirements. This device allows you to produce your own “specialty alloy” and enables you to change the chemistry to suit your application’s environment.

Request a quote today or contact Aero Metals for more information.

 

American Metal Testing