Stellite 25 Investment Casting High-Performance Turbine Vane Supplier
Introduction
Stellite 25 is a cobalt-chromium-tungsten-nickel superalloy engineered for high mechanical strength, excellent oxidation resistance, and structural stability at temperatures up to 980°C. As a specialist investment casting supplier, we produce precision Stellite 25 turbine vanes with dimensional accuracy within ±0.05 mm and consistent grain refinement, meeting the stringent requirements of gas and steam turbines operating under extreme thermal and mechanical loads.
Our cast components deliver long-term durability and performance, making them ideal for power generation and aerospace turbine systems.
Core Technology: Investment Casting of Stellite 25
Our Stellite 25 turbine vanes are manufactured using precision investment casting. The process includes multi-layer ceramic shell building (8–10 layers), vacuum melting and pouring at approximately 1450°C, and mold preheating between 1000–1100°C. Controlled solidification (cooling rate: 30–100°C/min) ensures homogeneous grain structure (0.5–2 mm), low porosity (<1%), and dimensional tolerances as tight as ±0.05 mm—crucial for aerodynamic and thermal efficiency in turbine applications.
Material Characteristics of Stellite 25 Alloy
Stellite 25 is a cobalt-based superalloy offering a superior combination of mechanical strength, oxidation resistance, and fatigue endurance at elevated temperatures. Key properties include:
Property | Value |
|---|---|
Melting Range | 1350–1410°C |
Density | 9.1 g/cm³ |
Tensile Strength (Room Temp.) | 980 MPa |
Yield Strength (Room Temp.) | 620 MPa |
Hardness (HRC) | 33–38 HRC |
Operating Temperature Limit | Up to 980°C |
Oxidation Resistance | Excellent (air and combustion) |
These properties make Stellite 25 a preferred material for turbine vanes exposed to hot gas streams, oxidation, and mechanical fatigue.
Case Study: Stellite 25 Turbine Vane Production
Project Background
A turbine OEM required high-performance vane segments capable of continuous operation at 950°C under high centrifugal and gas flow loads. Using investment casting, we produced Stellite 25 vanes for the second-stage high-pressure turbine section, with full compliance to ASTM F90 standards and internal quality benchmarks for aerospace-grade hardware.
Typical Turbine Vane Models and Applications
Gas Turbine Stator Vanes: Static vanes exposed to continuous high-temperature combustion gases, requiring creep resistance and oxidation stability at ~950°C.
Steam Turbine Nozzle Guide Vanes: Corrosion- and erosion-resistant vanes operating under high steam velocity and pressure fluctuations.
Aero-derivative Engine Vanes: High-strength vanes used in aviation-based turbines, engineered for weight savings and extreme fatigue resistance.
Industrial Powerplant Vanes: Durable components in base-load gas turbines subjected to long-term thermal and cyclic loading.
These vane types are critical for maintaining turbine thermal efficiency, flow control, and mechanical reliability.
Turbine Vane Manufacturing Solutions
Casting Process Wax patterns are injection molded and assembled into ceramic shell clusters. Following dewaxing, ceramic molds are sintered and vacuum cast at ~1450°C. Controlled solidification and pouring under vacuum maintain low turbulence and consistent grain orientation, reducing segregation and porosity to below 1%.
Post-processing Vanes undergo Hot Isostatic Pressing (HIP) at 1200°C and 100–120 MPa to eliminate micro-voids and improve creep resistance and mechanical uniformity.
Surface Treatment High-performance thermal barrier coatings (TBC), typically 7–8 wt% yttria-stabilized zirconia (YSZ), are applied via air plasma spray (APS). This coating reduces the metal surface temperature by up to 200°C, extending vane lifespan under hot gas exposure.
Testing and Inspection Critical testing includes digital X-ray inspection, CMM dimensional validation, and tensile testing at elevated temperatures. Grain structure and coating thickness are verified via metallographic analysis.
Core Manufacturing Challenges of Turbine Vanes
Maintaining ±0.05 mm dimensional tolerances across complex aerodynamic surfaces.
Achieving consistent surface finish and coating adhesion in high-flow gas regions.
Controlling porosity and microstructural uniformity across multiple casting batches.
Results and Verification
Our delivered Stellite 25 turbine vanes achieved:
Dimensional compliance verified through 100% CMM inspection.
<1% porosity confirmed via X-ray and HIP densification.
Tensile strength ≥980 MPa and oxidation resistance validated through 1000-hour high-temperature testing cycles.
FAQs
Why is Stellite 25 ideal for high-temperature turbine vane applications?
What dimensional tolerances can be achieved using investment casting?
How do you verify the structural integrity of turbine vane components?
Are Stellite 25 vanes suitable for both gas and steam turbine applications?
What coating options are available to extend vane service life in combustion environments?
