Ti-6.5Al-1Mo-1V-2Zr (TA15) Superalloy Casting High-Temperature Reactor Components Company
Introduction
Ti-6.5Al-1Mo-1V-2Zr, known as TA15, is a near-alpha titanium alloy developed for high-temperature structural applications requiring excellent creep resistance, thermal stability, and a moderate strength-to-weight ratio. As a specialized superalloy casting company, we manufacture precision TA15 components for high-temperature reactor systems using vacuum investment casting, achieving tight tolerances (±0.05 mm) and porosity below 1%.
TA15 castings are ideally suited for nuclear and aerospace energy systems, where long-term thermal resistance, dimensional stability, and reliability under load are critical.
Core Technology: Vacuum Investment Casting of TA15
TA15 components are produced using vacuum investment casting to ensure metallurgical integrity and oxidation control. The alloy is melted and poured at ~1650°C into ceramic shell molds (8–10 layers), with mold preheating at 1000–1050°C. Solidification rates of 30–70°C/min ensure grain refinement (0.5–2 mm), minimize shrinkage defects, and eliminate alpha-case contamination.
Material Characteristics of TA15 Alloy
Ti-6.5Al-1Mo-1V-2Zr (TA15) is a near-alpha titanium alloy featuring high-temperature oxidation resistance and exceptional creep strength. It is commonly used in hot section structures of aerospace and energy equipment. Key properties include:
Property | Value |
|---|---|
Density | 4.55 g/cm³ |
Ultimate Tensile Strength | ≥950 MPa |
Yield Strength | ≥880 MPa |
Elongation | ≥10% |
Creep Strength (1000h @ 500°C) | ≥180 MPa |
Operating Temperature Limit | Up to 550°C |
Oxidation Resistance | Excellent |
TA15’s strength retention at high temperature makes it ideal for reactor internals, structural enclosures, and thermal shielding parts.
Case Study: TA15 Reactor Component Production
Project Background
A nuclear thermal power developer required creep-resistant alloy enclosures and flange components for a modular high-temperature gas reactor (HTGR). TA15 was selected for its long-duration performance above 500°C. We delivered vacuum-cast components that met RCC-M nuclear specifications, with dimensional flatness of ±0.05 mm and grain structure optimized through post-casting heat treatment.
Typical High-Temperature Reactor Applications
HTGR Inlet Flanges: TA15 flanges designed for primary coolant loop connections in gas-cooled reactors such as HTR-PM, offering excellent sealing performance under thermal cycling.
Reactor Pressure Boundary Shields: Cast TA15 panels used to support and protect vessel internals against thermal and neutron-induced stress.
Helium Gas Diffuser Components: Oxidation-resistant cast structures exposed to high-velocity helium streams at >500°C in compact nuclear cores.
Fuel Handling Mechanism Frames: Lightweight, dimensionally stable castings providing precision alignment under variable thermal gradients in high-flux zones.
These parts maintain mechanical performance in corrosive, high-temperature reactor environments with minimal distortion over long operation periods.
Manufacturing Solutions for TA15 Components
Casting Process Wax patterns are formed and invested into ceramic shells, then vacuum cast at ~1650°C. Mold preheating and cooling rates are tightly controlled to avoid hot tearing and ensure full fill of complex shapes.
Post-processing Hot Isostatic Pressing (HIP) is performed at ~920°C and 100 MPa to reduce porosity. Aging and annealing cycles are applied to stabilize the alpha microstructure for long-term creep endurance.
Post Machining CNC machining is used for flanges, bolt interfaces, and sealing surfaces. EDM and deep hole drilling are applied to produce high-aspect cooling channels or access ports.
Surface Treatment To improve oxidation resistance, TA15 parts may receive anodizing or ceramic-based thermal barrier coatings. Shot peening is available to increase surface hardness and fatigue life.
Testing and Inspection All components undergo X-ray NDT, CMM dimensional validation, elevated-temperature tensile testing, and metallographic inspection to confirm microstructure, grain orientation, and phase stability.
Core Manufacturing Challenges
Achieving thin-wall castings without alpha-case or shrinkage cracking.
Maintaining dimensional tolerances in large cast panels subjected to thermal cycling.
Ensuring creep resistance and oxidation protection during 20,000+ hour operational lifespan.
Results and Verification
Dimensional flatness and roundness within ±0.05 mm verified by 3D CMM scanning.
Porosity <1% achieved post-HIP, confirmed by radiographic inspection.
Creep resistance ≥180 MPa at 500°C confirmed by long-duration testing.
Microstructural uniformity validated via SEM and optical metallography.
FAQs
What makes TA15 suitable for high-temperature nuclear and aerospace applications?
How is alpha-case formation avoided during titanium casting?
Can TA15 parts be customized for modular reactor designs like HTR-PM or VHTR?
What post-machining capabilities are available for TA15 castings?
What quality standards and testing procedures are followed for TA15 components?
