Tungsten 3D Printing:Specifications,Pricing,Pros

Tungsten and tungsten alloy powders enable printing high-density components with excellent mechanical and thermal properties using laser powder bed fusion (LPBF) and electron beam melting (EBM). This guide provides an overview of tungsten metal 3D printing.

Introduction to Tungsten 3D Printing

Tungsten is a unique material for additive manufacturing due to its:

• Exceptionally high density – 19 g/cm3
• High hardness and strength
• Excellent thermal conductivity
• High melting point of 3422°C
• Challenging processability and machinability

Key applications of printed tungsten parts:

• Radiation shielding
• Aerospace and motorsport components
• Radiotherapy devices and collimators
• Medical implants like dental posts
• Counterweights and balancing components
• Electrical contacts and heating elements

Common tungsten alloys for AM:

• Tungsten heavy alloys with Ni, Fe, Cu, Co
• Tungsten carbides
• Potassium doped tungsten oxides

Pure Tungsten Powder

Pure tungsten powder provides the highest densities:

Properties:

• Density of 19.3 g/cm3
• Excellent radiation blocking and shielding
• High hardness up to 400 Hv
• Strength up to 1200 MPa
• Melting point of 3422°C
• Good electrical and thermal conductivity

Applications:

• Medical radiation shielding
• X-ray collimators and appertures
• Aviation counterweights
• Vibration damping in motorsport
• Electrical contacts and heaters

Suppliers: TRU Group, Buffalo Tungsten, Midwest Tungsten

Tungsten Heavy Alloys

Tungsten heavy alloys with nickel, iron and copper provide ideal balance of density, strength and ductility:

Common grades:

• WNiFe (90W-7Ni-3Fe)
• WNiCu (90W–6Ni–4Cu)
• WNi (90W-10Ni)

Properties:

• Density of 17-18 g/cm3
• Strength up to 1 GPa
• Good corrosion and wear resistance
• High temperature strength

Applications:

• Automotive and motorsport components
• Aerospace and defense systems
• Vibration damping weights
• Radiation shielding
• Medical implants like dental posts

Suppliers: Sandvik, TRU Group, Nanosteel

Tungsten Carbides

Tungsten carbide powders print extremely wear resistant parts:

Types

• WC-Co hardmetals with 6-15% cobalt
• WC-Ni cemented carbides
• WC-CoCr cermets

Properties

• Hardness up to 1500 HV
• Compressive strength over 5 GPa
• High Young’s modulus
• Excellent abrasion and erosion resistance

Applications

• Cutting tools and drill bits
• Wear parts and seals
• Ballistic armor components
• Metal forming and stamping tools

Suppliers: Sandvik, Nanosteel, Buffalo Tungsten

Doped Tungsten Oxides

Potassium doped tungsten oxides like K2W4O13 provide unique electrical properties:

Characteristics

• Semiconducting behavior
• Electrical conductivity tunable with doping levels
• High density up to 9 g/cm3
• High radiation stability

Applications

• Electronics and electrical components
• Electrodes, contacts and resistors
• Thermoelectric generators
• Radiation detectors

Suppliers: Inframat Advanced Materials

Material Properties Comparison

Tungsten Powder Production Methods

1. Hydrogen Reduction

• Most common and economical process
• Tungsten oxide reduced by hydrogen
• Irregular powder morphology

2. Plasma Spheroidization

• Improves powder shape and flowability
• Done after hydrogen reduction
• Provides high purity

3. Plasma Atomization

• Superior powder sphericity and flow
• Control over particle size distribution
• Lower oxygen pickup than gas atomization

4. Chemical Vapor Synthesis

• Ultrafine nano-scale tungsten powders
• High purity with small particle sizes
• Used for tungsten oxide powders

Printer Technology for Tungsten

Laser Powder Bed Fusion (LPBF)

• High power fiber lasers > 400W
• Inert argon atmosphere
• Precise melt pool control critical

Electron Beam Melting (EBM)

• Powerful electron beam > 3kW
• High vacuum environment
• Most suited for highly dense materials

Binder Jetting

• Adhesive binder used to selectively join powder
• Post-processing needed for full density
• Lower part strength compared to LPBF and EBM

LPBF and EBM allow printing high-density tungsten components.

Technical Specifications

Typical tungsten powder specifications for AM:

Controlling powder characteristics like particle size distribution and morphology is critical for high density prints.

Print Process Development

Optimizing LPBF process parameters for tungsten:

• Preheating to control cracking – typ. 100-150°C
• High laser power > 400W with precise control
• Small layer thickness around 20-30μm
• Scanning strategies to minimize stresses
• Controlled cooling after printing

For EBM:

• Heating to >600°C to sinter powder
• High beam current with small point size
• Slower scan speeds for full melting
• Minimizing thermal gradients

Test prints are required to characterize properties.

Suppliers and Pricing

• Pure tungsten costs ~$350 to $850 per kg
• Heavy alloys cost ~$450 to $1000 per kg
• Doped oxides up to $1500 per kg

Pricing depends on purity, morphology, powder quality, and order volume.

Post-Processing

Typical post-processing steps for tungsten AM parts:

• Support removal using EDM or waterjet
• Hot isostatic pressing to eliminate voids
• Infiltration with lower-melt alloys
• Machining to improve surface finish
• Joining to other components if needed

Proper post-processing is vital to achieve final part quality.

Applications of Printed Tungsten Components

Aerospace: Turbine blades, satellite components, counterweights

Automotive: Balancing weights, vibration damping parts

Medical: Radiation shielding, collimators, dental implants

Electronics: Heatsinks, electrical contacts, resistors

Defense: Radiation shielding, ballistics protection

Printed tungsten components enable performance improvements in demanding applications across industries.

Pros and Cons of Tungsten AM

Advantages

• High density for radiation shielding
• Excellent strength and hardness
• Good thermal and electrical properties
• Customized geometries
• Consolidates multiple parts

Disadvantages

• Difficult and expensive to process
• Brittle material requiring supports
• Low ductility and fracture toughness
• Requires specialized equipment

Troubleshooting Printing Issues

FAQs

Q: What is the typical particle size used for tungsten printing powder?

A: 15-45 microns is common, with a tight control of the particle size distribution around 20-35 microns.

Q: What level of porosity can be expected in printed tungsten parts?

A: Less than 1% porosity is typically achieved through process optimization and hot isostatic pressing.

Q: What alloys provide a good balance of density and mechanical properties?

A: Tungsten heavy alloys with 6-10% Ni, Fe, and Cu provide high density with good ductility and fracture toughness.

Q: What post-processing is required on printed tungsten parts?

A: Support removal, hot isostatic pressing, infiltration, and machining are commonly used post-print processes.

Q: What preheating temperatures are used?

A: For LPBF, preheating up to 150°C is common to reduce residual stresses and cracking.

Q: What safety precautions are necessary when handling tungsten powder?

A: Use appropriate PPE, avoid inhalation, and follow safe powder handling procedures recommended by the supplier.

know more 3D printing processes

Q: What standards are used for qualifying tungsten printing powder?

A: ASTM B809, ASTM F3049, and MPIF Standard 46 cover chemical analysis, sampling, and testing.

Conclusion

Tungsten and its alloys enable additive manufacturing of high-density components with unrivaled stiffness, strength, hardness, and thermal properties using advanced 3D printing processes like LPBF and EBM. With its ultra-high melting point, density, and radiation blocking abilities, printed tungsten components find uses across aerospace, motorsport, medical, defense, and electronics applications. However, the challenging printability and post-processing requirements necessitate rigorous process control and parameter optimization to achieve full densification and ideal material properties. As expertise and experience in printing tungsten develops, its unique advantages can be leveraged to manufacture high-performance components with capabilities exceeding traditional manufacturing limitations.