Aerospace Investment Casting

The aerospace industry demands components that meet the most exacting standards of precision, reliability, and performance. Structural integrity must be maintained under extreme mechanical loads, wide temperature ranges, and highly corrosive environments — often simultaneously. Investment casting has been a cornerstone of aerospace manufacturing for decades, offering the design freedom, dimensional precision, and material versatility required to meet these demands in a way that no other manufacturing process can match.

Engineered Precision Casting Company has over 80 years of experience producing precision investment castings for aerospace customers. We are AS9100 registered and NADCAP approved for nondestructive testing, welding, heat treating, and hardness testing, providing the quality infrastructure that aerospace programs require.

Why Investment Casting for Aerospace?

Investment casting — also known as lost wax casting — produces near-net shape components with tight dimensional tolerances, excellent surface finish, and the ability to incorporate complex internal and external geometries that would be impossible or prohibitively expensive to achieve through machining or fabrication. For aerospace applications, these characteristics translate directly into reduced weight, lower part count, shorter lead times, and lower total cost of ownership.

Several properties make investment casting uniquely suited to aerospace manufacturing:

Dimensional precision — Investment castings routinely achieve tolerances of ±.005 inches per inch, reducing or eliminating secondary machining on critical features. For complex components that would otherwise require extensive multi-axis machining from solid billet, the cost savings are significant.

Complex geometry — Investment casting can produce thin-walled sections, internal passages, undercuts, and complex contoured surfaces in a single casting. This capability allows designers to consolidate multiple machined parts into a single casting, eliminating joints, fasteners, and assembly variation that can be sources of failure in critical applications.

Material versatility — Investment casting is compatible with virtually every aerospace alloy family, including stainless steel, precipitation hardening stainless steel, cobalt-base superalloys, nickel-base alloys, aluminum alloys, titanium, and carbon and low-alloy steels. This allows the optimal material to be selected for each application without compromise.

Surface finish — Investment castings produced by the lost wax process achieve surface finishes of 125 RMS or better in the as-cast condition, often eliminating the need for additional surface finishing on non-critical surfaces.

Repeatability — The investment casting process produces consistent, repeatable results from part to part and lot to lot, which is essential for aerospace programs requiring rigorous statistical process control and material traceability.

Aerospace Applications

Investment castings are found throughout modern aircraft, rotorcraft, and aerospace systems, from structural airframe components to propulsion hardware and mission-critical fluid systems.

Structural and Airframe Components

Investment castings are used extensively for structural brackets, fittings, housings, and frames where complex geometry, high strength-to-weight ratio, and dimensional consistency are required. Precipitation hardening stainless steels such as 17-4 PH and 15-5 PH are commonly specified for these applications, offering tensile strengths exceeding 180 ksi in the H900 condition with good corrosion resistance and minimal distortion during heat treatment. Aluminum investment castings — particularly A356 and A357 — are specified where weight reduction is the primary driver, delivering high strength in complex thin-walled geometries that would be impractical to machine from billet.

Propulsion and Engine Hardware

The demanding thermal and mechanical environment of aircraft engines and auxiliary power units places extraordinary demands on materials and manufacturing processes. Cobalt-base superalloys such as FSX-414, Cobalt #31, and Cobalt #25 are investment cast for hot section components including nozzle guide vanes, combustion hardware, transition ducts, and flame holders that must retain strength and resist oxidation at temperatures approaching 2000°F. Hastelloy X is specified for combustor cans, spray bars, and afterburner components where oxidation resistance and fabricability must be balanced. Nickel-base alloys including Inconel 600 and Inconel 625 are used for exhaust system components, housings, and structural hardware requiring a combination of high-temperature performance and corrosion resistance.

Fluid Systems and Valve Bodies

Aircraft fluid systems — including hydraulic, fuel, lubrication, and environmental control systems — rely heavily on investment castings for valve bodies, pump housings, manifolds, fittings, and actuator components. Stainless steel grades such as 316-L and 17-4 PH are the most commonly specified materials for these applications, offering the combination of corrosion resistance, pressure integrity, and dimensional precision that fluid system components demand. For applications involving highly corrosive media — such as oxygen systems or hydraulic fluids containing aggressive additives — Monel alloys (M35-1, M25S) provide the chemical resistance and non-magnetic properties required.

Landing Gear and Actuation Systems

Landing gear and actuation components are among the most mechanically demanding investment castings produced for aerospace applications. These parts must withstand high impact loads, repeated fatigue cycling, and exposure to hydraulic fluids and runway deicing chemicals. High-strength alloy steels such as 4330 and 4340, and precipitation hardening stainless steels in the H900 condition, are commonly investment cast for brackets, links, fittings, and actuator bodies in these systems. The ability to cast complex geometries with tight tolerances reduces the number of machining operations required on these high-value components.

Quality and Certification

Aerospace investment castings are produced under a rigorous quality management system. Engineered Precision Casting Company holds the following certifications relevant to aerospace customers:

AS9100 — Registered aerospace quality management system covering design, development, and production of investment castings for aerospace applications.

NADCAP — Approved for nondestructive testing, welding, heat treating, and hardness testing, covering the in-house secondary services most commonly required by aerospace customers on finished castings.

All castings are produced with full material traceability from raw material to finished part, with documentation packages available to meet customer and program requirements including chemical certifications, mechanical test reports, nondestructive testing results, and dimensional inspection reports.

Contact us to discuss your aerospace investment casting requirements, request a quote, or discuss alloy selection for your application.