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Ti-6Al-7Nb

Biocompatible titanium alloy offering high strength and corrosion resistance for additive manufacturing of medical implants and surgical devices.

Ti-6Al-7Nb is a medical-grade titanium alloy developed as a biocompatible alternative to Ti-6Al-4V. With niobium replacing vanadium, it offers superior corrosion resistance, improved cytocompatibility, and excellent mechanical strength for long-term implantation.

By using titanium 3D printing, Ti-6Al-7Nb enables the manufacturing of orthopedic and dental implants with tailored geometries and surface textures. Additive manufacturing enhances osseointegration, reduces weight, and enables customized solutions for patient-specific treatments.

Ti-6Al-7Nb Similar Grades Table

Country/Region	Standard	Grade or Designation
USA	ASTM	F1295 Grade 1
USA	UNS	R56700
ISO	ISO 5832-11	Ti-6Al-7Nb
China	GB	TC20

Ti-6Al-7Nb Comprehensive Properties Table

Category	Property	Value
Physical Properties	Density	4.50 g/cm³
	Melting Range	1600–1650°C
	Thermal Conductivity (20°C)	6.4 W/(m·K)
	Thermal Expansion (20–500°C)	8.7 µm/(m·K)
Chemical Composition (%)	Titanium (Ti)	Balance
	Aluminum (Al)	5.5–6.5
	Niobium (Nb)	6.5–7.5
	Oxygen (O)	≤0.15
	Iron (Fe)	≤0.25
Mechanical Properties	Tensile Strength	≥900 MPa
	Yield Strength (0.2%)	≥820 MPa
	Elongation at Break	≥15%
	Modulus of Elasticity	110 GPa
	Hardness (HRC)	28–34

3D Printing Technology of Ti-6Al-7Nb

Ti-6Al-7Nb is compatible with Selective Laser Melting (SLM), Direct Metal Laser Sintering (DMLS), and Electron Beam Melting (EBM). These methods support the production of porous and solid implants with precise control over structure, fit, and strength.

Applicable Process Table

Technology	Precision	Surface Quality	Mechanical Properties	Application Suitability
SLM	±0.05–0.2 mm	Excellent	Excellent	Orthopedic Implants, Dental
DMLS	±0.05–0.2 mm	Very Good	Excellent	Trauma Plates, Custom Screws
EBM	±0.1–0.3 mm	Good	Very Good	Load-Bearing, Lattice Structures

Ti-6Al-7Nb 3D Printing Process Selection Principles

For patient-specific implants requiring dimensional accuracy (±0.05–0.2 mm) and fine surface detail (Ra 5–10 µm), SLM provides optimal control over geometry and pore structures to promote osseointegration.

DMLS is suited for orthopedic hardware and surgical components with complex forms, offering consistent mechanical properties and surface quality.

EBM is advantageous for producing large, porous implants and load-distributing frameworks with moderate precision and high throughput.

Ti-6Al-7Nb 3D Printing Key Challenges and Solutions

Thermal stress from localized melting can affect implant shape and fatigue life. Using robust support structures and post-process Hot Isostatic Pressing (HIP) at 900–940°C and 100–150 MPa relieves stress and densifies microstructure.

Porosity, if uncontrolled, may lead to strength reduction. Laser parameter optimization (power: 250–350 W, speed: 600–900 mm/s) combined with HIP ensures >99.9% density while preserving open porosity where designed.

Surface roughness (Ra 8–15 µm) can interfere with tissue compatibility. Electropolishing and CNC machining improve the surface to Ra 0.4–1.0 µm, meeting ISO 5832-11 for medical-grade finishes.

Powder must be protected from oxidation. Controlled environments with oxygen < 200 ppm and relative humidity < 5% maintain ELI-grade purity for safe, implantable use.

Industry Application Scenarios and Cases

Ti-6Al-7Nb is used primarily in:

Medical: Hip stems, dental implants, trauma fixation systems, and spinal cages.
Surgical Tools: Corrosion-resistant, lightweight handles and forceps.
Aerospace (secondary): Where biocompatibility and weldability are valued in support systems.

A recent orthopedic case used SLM to fabricate porous Ti-6Al-7Nb acetabular cups, achieving optimized bone ingrowth, 50% weight reduction, and shortened surgical prep time through direct patient-matching.