Ti22Al25Nb Powder:Standards,Types,Specifications

Overview of Ti22Al25Nb Powder

Ti22Al25Nb is an alpha-2 titanium aluminide alloy powder containing 22% aluminum, 25% niobium and the balance titanium. It exhibits an attractive combination of properties:

  • Low density – 3.7 g/cm3, almost half that of nickel superalloys
  • Excellent high temperature strength and creep resistance
  • Good oxidation and corrosion resistance
  • Capability for service temperatures up to 750°C

These characteristics make Ti22Al25Nb suitable for manufacturing lightweight, high-performance components for aerospace, automotive, and other applications via additive manufacturing or powder metallurgy.

Types of Ti22Al25Nb Powder

Ti22Al25Nb alloy powder can be categorized into the following main types based on production method and morphology:

TypeDescriptionParticle ShapeSize RangeProduction Method
Gas AtomizedIrregular spheroidal powderMostly spherical15-75 μmGas atomization
Plasma AtomizedHighly spherical powderHighly spherical10-45 μmPlasma atomization
BlendedMixture of gas atomized and irregular particlesMixed morphology15-125 μmMechanical blending
AlloyedPrealloyed powder with homogeneous compositionSpherical or irregular15-105 μmGas/plasma atomization of prealloyed melt

Plasma atomized and prealloyed powders offer more homogeneous properties but are costlier. Blended and gas atomized powders provide a cheaper option.

Overview of Ti22Al25Nb Powder

Ti22Al25Nb is an alpha-2 titanium aluminide alloy powder containing 22% aluminum,

Characteristics and Properties of Ti22Al25Nb Powder

Ti22Al25Nb demonstrates an exceptional mix of physical, mechanical, and thermal properties:

PropertyDescription
Density3.7 g/cm3
Melting Point1540°C
Electrical Resistivity182 μΩ-cm
Young’s Modulus151 GPa
Poisson’s Ratio0.34
Tensile Strength500-900 MPa
Compressive Strength1000-1600 MPa
Hardness350-450 HV
Fracture Toughness25-35 MPa-m^1/2
Thermal Conductivity24 W/m-K
Thermal Expansion Coefficient11 x 10^-6 K^-1
Oxidation ResistanceExcellent up to 750°C

The properties make it suitable for high-stress elevated temperature applications in corrosive environments across sectors.

Applications of Ti22Al25Nb Alloy Powder

Ti22Al25Nb powder can be used to fabricate components for the following applications:

Aerospace: Turbine blades, discs, casings, heat shields, engine parts

Automotive: Turbocharger wheels, valves, connrods, springs, exhaust components

Industrial Gas Turbines: Combustor liners, nozzles, rotors, casings

Chemical Industry: Valves, pumps, heat exchangers for corrosive environments

Biomedical: Orthopedic and dental implants, surgical instruments

Sports & Leisure: Golf club heads, bicycle parts, motorcycling components

Electronics: Lead frames, connectors, packaging for thermal management

Energy: Nuclear, geothermal, solar thermal equipment demanding high temperature strength

The low density and high temperature properties provide significant benefits over conventional nickel and steel alloys in reducing weight and improving efficiency.

Specifications of Ti22Al25Nb Powder

Ti22Al25Nb powder must conform to the following specifications:

ParameterSpecificationTest Method
Particle size15-150 μmLaser diffraction, sieve analysis
Particle shapeSpherical, angular, or blendedSEM imaging
Apparent density> 2.5 g/cm3ASTM B212
Tap density> 3.5 g/cm3ASTM B527
Flow rate> 25 s/50gASTM B213
CompositionAl 20-23 wt%, Nb 23-27 wt%, Ti balanceICP-OES
Oxygen content< 2000 ppmInert gas fusion
Nitrogen content< 500 ppmInert gas fusion
Carbon content< 1000 ppmCombustion analysis
Hydrogen content< 100 ppmInert gas fusion

The requirements ensure high powder quality for additive manufacturing, metal injection molding, and press and sinter processing.

Design Considerations for Ti22Al25Nb Parts

Several design factors must be optimized when using Ti22Al25Nb powder:

  • Minimum wall thickness should be 1-2 mm to ensure sufficient strength
  • Generous fillets and tangent transitions should be used to avoid stress concentrations
  • Draft angles ≥ 2° are recommended for ease of powder removal
  • As-sintered surfaces will have lower finish than wrought products; post-processing may be required
  • Dimensional tolerances down to ±0.2% are possible but ±0.5-1% is more typical
  • A sintered density ≥ 95% is needed to achieve mechanical properties close to wrought alloys
  • Heat treatment can be used to further enhance strength through precipitation hardening
  • Critical features may need post-processing through hot isostatic pressing or machining

Careful consideration of these aspects during design enables high performance Ti22Al25Nb parts to be manufactured successfully and economically using powder metallurgy techniques.

Standards for Ti22Al25Nb Powder

Ti22Al25Nb powder must comply with the following standards:

StandardDescription
ASTM B981Standard specification for titanium alloys in powder form for MIM
EN 10204Chemical analysis and test report requirements
ISO 9001Quality management system requirements
ISO 13485Quality management for medical devices
AMS 4967Composition limits for titanium alloy powder

Certification to standards for chemistry, quality systems, and testing provides assurance to customers that the powder meets specifications for the target application. Medical and aerospace applications have additional requirements.

Suppliers of Ti22Al25Nb Powder

Some leading global suppliers of Ti22Al25Nb powder include:

SupplierParticle SizeProduction MethodKey Features
AP&C15-45 μmPlasma atomizationHighly spherical, prealloyed
TLS Technik10-75 μmGas atomizationCost-effective irregular powder
Sandvik Osprey45-150 μmGas atomizationBlended and prealloyed options
Praxair15-105 μmGas atomizationCapacity for large orders
Carpenter Additive15-75 μmGas atomizationOptimized particle size distribution

Factors like lead time, minimum order quantity, and location should also be considered when selecting a supplier. Some additional customization of powder may be needed to meet application requirements.

Pricing Estimates for Ti22Al25Nb Powder

Ti22Al25Nb powder is more expensive than titanium grades like Ti-6Al-4V due to higher niobium content and lower production volumes:

Powder GradeParticle SizePrice Range
Irregular15-75 μm$200-300/kg
Spherical15-45 μm$250-450/kg
Alloyed15-75 μm$300-500/kg
Plasma Spheroidized15-45 μm$400-600/kg
  • Prices decline significantly for bulk orders exceeding 100 kg.
  • Special screening or blending to customize particle size distribution commands a premium.
  • Premium spherical and prealloyed powders carry higher pricing.
  • Quoted prices may fluctuate over time due to raw material and energy costs.

Installation and Maintenance of Ti22Al25Nb Powder Equipment

Special practices should be followed when installing powder handling systems and processing Ti22Al25Nb powder:

ActivityProcedure
StorageStore sealed containers in a dry (<50% RH) environment at 18-25°C. First-in-first-out inventory management.
HandlingUse appropriate PPE – gloves, respirator, goggles. Carefully pour powder to avoid spills. Ground all equipment.
InstallationQualify and validate all equipment. Check weighing, mixing, feeding, and sieving operation.
ProcessingClosely follow all parameter guidelines provided. Frequently check powder condition.
MaintenanceEstablish preventive maintenance schedule. Check seals, controls, filters periodically. Promptly address anomalies.
SafetyEnsure fire suppression and explosion prevention systems are operational. Install blast walls if needed.

Proper installation, operation, and maintenance are vital for safe handling of titanium powder and preventing process disruptions.

Ti22Al25Nb Powder

Selecting a Ti22Al25Nb Powder Supplier

Here are key factors to consider when selecting a Ti22Al25Nb powder supplier:

  • Technical expertise in titanium powder production including alloying, gas atomization, quality control
  • Range of powder types and sizes – spherical, prealloyed, blended, various particle size distributions
  • Quality certifications – ISO 9001, ISO 13485, AS9100, etc. indicating rigorous quality control
  • Batch testing capabilities – chemical assay, particle size analysis, microscopy, density, flow rate
  • Customization capability – ability to provide special particle characteristics or tight tolerances
  • Pricing – competitive pricing for both high and low volume purchases
  • Lead time – short lead times essential for fast-paced research and prototyping
  • Inventory – some stock availability for standard powders to avoid lead times
  • Customer service – responsive technical support and open communication
  • Distribution network – geographic proximity for reduced shipping time and cost

Established titanium powder producers with a broad product portfolio and inventory tend to best meet requirements.

Pros and Cons of Ti22Al25Nb Powder

Advantages

  • Very high strength-to-weight ratio
  • Excellent high temperature mechanical properties
  • Good corrosion and oxidation resistance
  • Enables lightweight engineered components
  • Components can replace heavy steel or nickel parts
  • Cost-effective compared to other titanium alloys
  • Established supplier base for quality powder

Disadvantages

  • Higher cost than steel, aluminum or nickel alloy powders
  • Challenging to process due to reactivity of titanium
  • Brittle behavior limits cold forming and machining
  • Requires high levels of process control and operator skill
  • Post-processing often needed to achieve final part properties
  • Limited number of suppliers compared to common alloys

For applications where the benefits of low density and temperature capability outweigh the higher cost, Ti22Al25Nb powder is an attractive choice. But processing does require stringent controls.

Comparison of Ti22Al25Nb, TA15, and Ti6Al4V Powders

Ti22Al25Nb sits between TA15 and Ti6Al4V in terms of properties:

AlloyDensityStrengthDuctilityOxidation ResistanceUse TemperatureCost
Ti22Al25NbLowHighMediumGoodHighHigh
TA15Very lowMediumLowExcellentVery highVery high
Ti6Al4VMediumMediumHighModerateMediumLow
  • Ti22Al25Nb provides the best all-round combination of strength, temperature capability, oxidation resistance and cost.
  • TA15 is used for extreme temperature applications but is more brittle.
  • Ti6Al4V offers higher ductility but lower service temperatures.

Thus, Ti22Al25Nb provides an optimal balance for most critical aerospace rotating components, turbine blades, and other high-performance applications.

Ti22Al25Nb Powder

FAQ

What are the main benefits of Ti22Al25Nb over nickel superalloys?

Ti22Al25Nb offers a 40-50% lower density along with competitive high temperature mechanical properties up to 750°C. This provides significant weight savings.

What particle size range is recommended for additive manufacturing with Ti22Al25Nb?

A particle size range of 15-75 μm is typically recommended, with a majority between 45-75 μm, to achieve good powder bed packing and spreading. Finer particles below 10 μm can cause challenges.

Is hot isostatic pressing required after additive manufacturing with Ti22Al25Nb?

While not always necessary, HIPing can help maximize density, refine microstructure, and improve mechanical properties. HIP is recommended for critical aerospace components.

What type of powders provide the most homogeneous properties in Ti22Al25Nb?

Prealloyed gas or plasma atomized powders offer the most homogeneous distribution of alloying elements and stable properties.

How should Ti22Al25Nb powder be stored?

Ti22Al25Nb powder is highly reactive and must be stored in sealed containers under an inert argon atmosphere with moisture levels below 50% RH. Temperatures should be between 18-25°C.

What safety precautions are necessary for handling Ti22Al25Nb powder?

An enclosed system under inert gas, adequate PPE including respirators, electrically grounding all equipment, proper training of personnel, and fire suppression systems are essential when handling reactive titanium powder.

know more 3D printing processes

Share This Post:

Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents

Most Popular

Get In Touch

Get in touch with us

On Key

Related Posts

TA15 Titanium Alloy Powder

TA15 Titanium Alloy Powder

In the realm of advanced materials, titanium alloys reign supreme for their exceptional blend of strength, weightlessness, and resilience. But within this metallic kingdom, TA15 titanium alloy powder stands out

Read More »
Ti-6Al-4V Powder

Ti-6Al-4V Powder

Imagine a material that’s incredibly strong yet surprisingly lightweight, shrugging off corrosion like a seasoned warrior. That’s the magic of Ti-6Al-4V powder, a game-changer in the world of advanced manufacturing.

Read More »
pure aluminum powder

pure aluminum powder

Imagine a metal so light it floats, yet strong enough to be a crucial component in rockets and explosives. That’s the fascinating world of pure aluminum powder, a versatile material

Read More »
AlSi7Mg Powder

AlSi7Mg Powder

Imagine building complex, high-strength components with incredible detail, all while keeping weight to a minimum. That’s the magic of AlSi7Mg powder, a revolutionary material taking the world of additive manufacturing

Read More »
small_c_popup.png

Let's have a chat

Get In Touch With Us