Titanium Powders:Production,Characteristics,

Overview

Titanium powder is a versatile metallic material valued for its unique combination of high strength, low density, corrosion resistance, and biocompatibility. As a powder, titanium facilitates advanced manufacturing techniques like metal injection molding (MIM), additive manufacturing (AM), hot isostatic pressing (HIP), and powder metallurgy (PM) pressing and sintering to create complex titanium components.

Key applications for titanium powder include aerospace components, medical implants, automotive parts, sporting equipment, chemical processing, and consumer products. This guide provides a comprehensive overview of titanium powder, including production methods, alloy compositions, characteristics, properties, specifications, applications, and global suppliers. It aims to assist engineers, product designers, and technical program managers in selecting and using titanium powders.

Production of Titanium Powder

Titanium powder is produced using the following primary methods:

Titanium Powder Production Methods

• Gas Atomization – High pressure inert gas disintegrates molten titanium into spherical powder
• Plasma Atomization – Titanium electrode arcs create ultrafine spherical powder
• Hydriding/Dehydriding – Titanium hydride powder (TiO2) is dehydrided into fine powders
• Mechanical Milling – Ball milling breaks down titanium chips into irregular particles
• Plasma Spheroidization – Irregular powder melted in plasma to produce spherical shapes

Gas atomization and mechanical milling are most common, creating spherical and angular powder shapes respectively. Additional screening, conditioning, and blending create application-specific particle size distributions.

Compositions of Titanium Powder

While commercially pure titanium powders are available, most powders for industrial uses contain small amounts of alloying elements:

Common Titanium Powder Compositions

Alloy	Primary Alloying Elements	Key Characteristics
CP Titanium	99.5%+ Ti	Excellent corrosion resistance
Ti-6Al-4V	6% Al, 4% V	High strength, heat treatable
Ti-6Al-7Nb	6% Al, 7% Nb	High strength, biocompatible
Ti-555	5% Al, 5% Mo, 5% V	Heat treatable, machinable
Ti-1023	10% V, 2% Fe, 3% Al	High strength, good ductility

Aluminum, vanadium, and niobium are common additions to enhance strength and workability. Trace boron, carbon, iron, and oxygen also appear.

Alloying tailors microstructure, hardness, machinability, and other properties while retaining excellent corrosion resistance.

Characteristics of Titanium Powders

Key characteristics of titanium powder include:

Titanium Powder Characteristics

Characteristic	Typical Values	Significance
Particle size	10 – 150 microns	Sintering behavior, surface finish
Particle shape	Spherical, angular, dendritic	Powder flow and packing density
Apparent density	1.5 – 4.0 g/cc	Pressing and handling behavior
Tap density	2.5 – 4.5 g/cc	Indicator of compressibility
Hall flow rate	25 – 35 s/50g	Powder flowability
Loss on ignition	0.1 – 0.5 wt%	Oxygen and moisture content
Pyrophoricity	None	Flammability and handling precautions

Particle size distribution and powder shape significantly impact powder flow, compaction, sintering response, and density of pressed and sintered parts. Apparent density indicates powder compressibility.

Properties of Titanium Powders

Key titanium powder properties include:

Titanium Powder Properties

Property	Pure Ti	Ti-6Al-4V	Ti-6Al-7Nb
Density	4.5 g/cc	4.43 g/cc	4.52 g/cc
Tensile Strength	240 MPa	930 MPa	900 MPa
Yield Strength	170 MPa	860 MPa	825 MPa
Elongation	24%	10%	15%
Elastic Modulus	102 GPa	114 GPa	105 GPa
Hardness	80 HB	334 HB	321 HB
Heat Capacity	522 J/kg·K	526 J/kg·K	527 J/kg·K
Thermal Conductivity	7.2 W/m·K	7.2 W/m·K	6.7 W/m·K

Alloying with aluminum, vanadium, and niobium enhances strength and hardness significantly. Specific properties depend heavily on final microstructure.

Applications of Titanium Powder

Key applications for titanium powder include:

Titanium Powder Applications

Industry	Uses	Key Reasons
Aerospace	Structural components, turbine blades, fasteners	High strength-to-weight ratio
Medical	Orthopedic implants, dental implants, surgical tools	Biocompatibility, corrosion resistance
Automotive	Connecting rods, valves, springs, fasteners	Light weighting, performance
Chemical	Tanks, pipes, valves, pumps	Corrosion resistance
Sporting goods	Golf clubs, bicycles, helmets	Strength, tailored mechanical properties
Petrochemical	Downhole tools, wellhead parts	Strength, corrosion resistance

Titanium’s unique properties make it attractive for reducing weight in aerospace components while maintaining mechanical integrity in extreme environments.

Excellent biocompatibility and corrosion resistance drive usage in orthopedic and dental implants. The ability to tailor titanium’s properties facilitates sporting goods with specialized performance characteristics.

Specifications for Titanium Powders

Titanium powder compositions and quality are defined by various standard specifications:

Titanium Powder Standards

Standard	Scope	Particle Size	Purity	Chemistry
ASTM B348	Grade 1-4 unalloyed Ti powder	-635 mesh	99.5%, 99.9%, 99.95% Ti	O, C, N, H limits
ASTM B801	Ti-6Al-4V alloy powder	-635 mesh	Ti, Al, V composition ranges	Interstitial limits
ISO 23301	Additive manufacturing Ti powder	10-45 microns	99.5%+ Ti	O, N, C, H, Fe limits
AMS 4992	Aerospace grade Ti-6Al-4V powder	-150 mesh	Ti, Al, V composition ranges	Interstitial limits

These define acceptable levels of alloying additions, impurities like oxygen/nitrogen/carbon, particle size distributions, and other test methods relevant for different applications.

Global Suppliers of Titanium Powders

Many major corporations produce titanium powders along with smaller regional manufacturers:

Titanium Powder Manufacturers

Supplier	Production Methods	Materials	Capabilities
ATI Metals	Gas atomization	Ti-6Al-4V, Ti-1023, pure Ti	Wide alloy range, large volumes
Praxair	Gas atomization	Ti-6Al-4V, CP Ti	Small lots, rapid delivery
Carpenter Additive	Gas atomization, hydride-dehydride	Ti-6Al-4V, Ti-6Al-7Nb, pure Ti	Custom alloys, small lots
AP&C	Plasma atomization	CP Ti, Ti alloys	Ultrafine 10-45 micron powder
Tekna	Plasma spheroidization	Ti-6Al-4V, CP Ti	Convert chips into spherical powder
Baoji Hanz Titanium	Hydriding	CP Ti, Ti-6Al-4V	Low costChinese producer

Many supply both standard and custom alloy compositions. Some provide toll processing of scrap and chips into powder.

Selecting Titanium Powder

Key considerations for selecting titanium powder include:

• Alloy composition – Balances desired properties like strength, ductility, hardness
• Purity level – Affects mechanical properties and microstructure
• Particle size and shape – Influences powder flow, density, surface finish
• Apparent and tap density – Indicates compressibility and sintering response
• Chemical compatibility – For service conditions like acids or salt water
• Sampling procedures – Representative testing of powder lots
• Quality certifications – ISO 9001, AS9100, etc.
• Technical expertise from powder producer

Samples builds and prototypes help qualify new alloys and powders for a given application. Work closely with reputable suppliers to obtain well-characterized titanium powder for optimal results.

FAQ

What is the benefit of plasma atomized titanium powder?

Plasma atomization produces very spherical, flowing particles typically 10-45 microns in size. This allows excellent sintered density and surface finish.

What causes titanium powder to be pyrophoric?

Pyrophoric titanium powders ignite spontaneously in air. This is caused by extremely small particle sizes below 10 microns which greatly increase surface area and reactivity. Use inert gas handling for pyrophoric powders.

How does particle shape influence titanium powder properties?

Spherical powder flows well and provides higher and more uniform density and mechanical properties. Irregular powder offers better green strength and compressibility but less predictable shrinkage.

What post-processing can improve titanium powder reuse?

Screening, milling, and thermal treatments allow reuse of off-spec powders. Plasma spheroidization converts chips and coarser particles into spherical powder feedstock.

What standards apply to additive manufacturing of titanium parts?

ASTM F3001-14 covers characterization and quality control of Ti alloy powder for AM. ASTM F2924-14 gives standard test methods for evaluating mechanical properties of AM titanium.

Can you 3D print a titanium and steel composite structure?

Yes, some metal 3D printing processes transition between titanium and stainless steel alloys within one part by precise material switching to build bimetallic components.

Conclusion

Titanium powder provides engineers great flexibility to build high performance components thanks to the metal’s unique properties. Careful selection of powder characteristics and close collaboration with experienced suppliers enables optimal results across many critical applications. Ongoing advances continue to expand the capabilities, quality, and cost-effectiveness of titanium powder metallurgy processes.

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