Not many alloys can survive in the environment downstream of the combustion chamber in a gas turbine engine. It’s too hot, forces are high, the gases are extremely corrosive and they’re flowing quickly. Together, these factors make material selection one
In a gas turbine engine the nozzle assembly comes just after the combustion chamber. It directs fast moving gasses onto the turbine blades that generate the rotary motion needed for power generation. It’s a complex piece of engineering, produced in
Stainless steel is produced in a large number of grades that have austenitic, ferritic or martensitic structures. 17-4 is a martensitic grade that can be precipitation hardened, (leading to the 17-4 PH designation). It’s often investment cast and is a
Wall thickness refers to the distance between opposite sides or surfaces of a solid metal cast region. In a part like a cover the wall thickness is the distance between inner and outer surfaces. Thin walls are difficult to cast,
The heart of the axial flow turbine engine is the combustion chamber. This is where fuel and air are mixed and ignited, with air velocity determining how far through the chamber the flame front extends. Parts used in the combustion
Stainless steel is preferred for many aircraft engine, structural, fuel and hydraulic system applications. Providing a combination of strength and corrosion-resistance, it supports weight reduction goals and facilitates factors of safety of 1.5. Part mass is minimized by investment casting.
Gas turbine nozzle components are some of the most highly engineered parts manufactured anywhere. They need to survive high temperatures, corrosive atmospheres, vibration and centrifugal forces, and the challenges are growing as gas turbine manufacturers push for higher temperatures and
One of the reasons for having parts made by investment casting is that the process is capable of maintaining tight tolerances. This minimizes secondary machining and enables reproduction of fine. What’s left unasked though is, what tolerances can investment casting
If you’re looking for a North American source of investment castings, Impro can help. We started investment casting at our plant in Mexico in late 2022, and with extensive precision machining services on site, we’re able to finish as well
Engineers turn to nickel-based superalloys when stainless steel can’t provide enough corrosion resistance or high temperature strength. The downside of alloys like Inconel® though, is that they are hard to machine. This makes investment casting the most practical manufacturing route.
The combustion gases expelled from a gas turbine will quickly erode and can even melt most steels. For internal components to survive in such an environment, they are investment cast in nickel-based superalloys, precision machined and carefully inspected. Here’s an
Investment casting is ideal for producing parts that will be highly loaded, subjected to high temperatures and pressures, or require precise geometry that minimizes secondary operations. This is especially true when the alloys used are expensive and hard to machine.