Inconel 738LC Superalloy Equiaxed Crystal Casting Compressor Blades Service
Introduction
Compressor blades in gas turbines and jet engines experience high rotational speeds, fluctuating pressure loads, and elevated temperatures. These components must maintain dimensional stability, fatigue strength, and oxidation resistance during long service cycles. Inconel 738LC, a low-carbon version of the standard Inconel 738 alloy, offers improved weldability, reduced cracking sensitivity, and superior mechanical performance at high temperatures.
Neway AeroTech provides precision equiaxed crystal casting of Inconel 738LC compressor blades using vacuum investment casting and AS9100-compliant manufacturing processes. Our services support aerospace, power generation, and marine turbine applications requiring strong, oxidation-resistant compressor airfoils.
Core Technology of Inconel 738LC Equiaxed Casting for Compressor Blades
Wax Pattern Fabrication Blade profiles, root forms, and cooling details are replicated via wax injection molding with ±0.05 mm tolerance.
Shell Mold Construction Multilayer ceramic molds (6–8 mm thick) are built for dimensional precision and thermal control during solidification.
Vacuum Induction Melting Inconel 738LC alloy is melted under vacuum (≤10⁻³ Pa) at ~1450°C, preventing oxidation and maintaining chemical homogeneity.
Equiaxed Solidification Alloy solidifies under controlled thermal conditions to form randomly oriented, equiaxed grains (ASTM 5–7), ensuring isotropic mechanical properties.
Shell Removal and Cleaning Post-casting, molds are removed with blasting and leaching techniques that preserve surface quality and blade geometry.
Heat Treatment Solution and aging treatment promote uniform γ′ precipitation, enhancing creep strength and oxidation resistance.
Final Machining Critical surfaces such as root faces, dovetails, and shrouds are finished using CNC machining and EDM.
Quality Inspection Blades are verified by CMM, X-ray, and ultrasonic testing to ensure dimensional and structural integrity.
Inconel 738LC Material Properties for Compressor Blade Applications
Maximum Operating Temperature: 1050°C
Tensile Strength: ≥1000 MPa
Yield Strength: ≥850 MPa
Creep Rupture Strength: ≥200 MPa at 850°C (1000 hrs)
Oxidation Resistance: Excellent under high-speed airflow and elevated temperatures
Weldability: Improved over standard Inconel 738 due to reduced carbon
Grain Structure: Equiaxed (ASTM 5–7), isotropic mechanical properties
Case Study: Equiaxed Cast Inconel 738LC Blades for Aeroengine Compressor Section
Project Background
Neway AeroTech delivered equiaxed-cast Inconel 738LC compressor blades for a mid-stage compressor rotor in a commercial aircraft engine. The blades were designed to withstand temperatures up to 900°C and operate at high RPMs with minimal creep deformation. Requirements included consistent microstructure, tight tolerance on blade airfoils, and fatigue resistance.
Typical Applications
Mid- and Rear-Stage Compressor Blades Operate under moderate to high temperatures and high mechanical stress with exposure to oxidation and vibration.
Marine Gas Turbine Compressors Require salt-resistant, fatigue-tolerant blades for stable performance in shipboard environments.
Industrial Gas Turbine Compression Stages Support continuous operation with minimal maintenance under variable load and fuel conditions.
Manufacturing Workflow for Inconel 738LC Compressor Blades
DFM and CFD Optimization CFD analysis ensures optimized flow geometry and minimizes casting defects like shrinkage or segregation.
Vacuum Casting Process Inconel 738LC is cast under vacuum conditions to produce high-quality equiaxed blades with low porosity and consistent grain structure.
Heat Treatment and Phase Stabilization Solution aging achieves a stable γ′ phase structure, critical for high-cycle fatigue and long-term thermal exposure.
CNC Finishing and EDM Root forms, locking features, and flow passage edges are completed with CNC machining and EDM.
Dimensional and NDT Inspection Each blade undergoes CMM inspection, X-ray, and ultrasonic testing to ensure compliance with aerospace standards.
Key Challenges
Controlling microstructure across varying cross-sections
Minimizing warpage during post-casting heat treatment
Achieving tight dimensional tolerances in aerodynamic profiles
Preventing cracking or distortion during CNC finishing
Results and Verification
ASTM 6 grain structure confirmed across full blade profiles
Dimensional tolerance maintained within ±0.03 mm on airfoils and roots
Creep resistance exceeded 200 MPa at 850°C for 1000 hours
100% batch compliance with X-ray and ultrasonic inspection standards
Final blades delivered with complete material and process traceability
FAQs
What makes Inconel 738LC suitable for compressor blade applications?
How does equiaxed casting support compressor blade fatigue resistance?
What inspection methods ensure quality in cast Inconel blades?
Can Inconel 738LC compressor blades be repaired or welded?
How do you control grain size and phase stability during casting?
