This document discusses nanostructured titanium for use in dental implants developed by COMTES FHT. It summarizes that COMTES FHT uses severe plastic deformation through continuous extrusion and rotary swaging to refine titanium grains down to the nano scale. This nanostructured titanium of grades 2 and 4 achieves higher mechanical properties than commercial grades, with grade 2 reaching properties of grade 4 and grade 5 and grade 4 exceeding grade 5. Nanostructured titanium allows improving dental implant strength and toughness without compromising biocompatibility.

1. www.comtesfht.cz
Nanostructured titanium for dental
implants
Pavel Šuchmann, COMTES FHT a.s.

2. www.comtesfht.cz
COMTES FHT – brief introduction
 private research institute
 established in 2000 as a small engineering office
(5 engineers)
 currently 75 employees, projects in EU, India,
China, USA etc.

3. www.comtesfht.cz
COMTES FHT - activities
 Development of alloys and their processing technologies (casting,
forming, heat treatment etc.)
 Prototyping, verification of new technologies in field conditions
 Testing of mechanical and thermophysical
properties, measurement of complex materials
data
 Metallographic analyses, fractography etc.

4. www.comtesfht.cz
Dental implants - requirements
 biocompatibility
 high strength and toughness
 high precision of geometry
Most dental implants are made of titanium

5. www.comtesfht.cz
Market situation in titanium dental implants
 Only few titanium allyos are certified on biocompatibility
 High strength of implants is required because of low cross sections
 No strengthening via heat treatment possible
 Limited application of Ti gr. 5 in the last time because of problematic
biocompatibility although the material is certified (contains Al, V)
ASTM grade (W. Nr.) Fe O N C H Al V UTS [MPa]
Ti grade 1 (3.7025) 0.15 0.12 0.05 0.06 0.013 - - 240
Ti grade 2 (3.7035) 0.20 0.18 0.05 0.06 0.013 - - 440
Ti grade 3 (3.7055) 0.25 0.25 0.05 0.06 0.013 - - 540
Ti grade 4 (3.7065) 0.30 0.35 0.05 0.06 0.013 - - 650
Ti grade 5 (3.7165) 0.30 0.20 0.05 0.08 0.015 5.5 – 6.75 3.5 – 4.5 920
Limited options to achieve
strength of > 650 MPa
together with very good
biocompatibility

6. www.comtesfht.cz
Technical approach
 Grain boundary strengthening (using of Hall-Petch relationship)
6
Laboratory experiment
Equal Channel Angular
Pressing – ECAP Industrial process
Continuous extrusion on
CONFORM machine

7. www.comtesfht.cz
Nanostructured Ti for high strength applications
 technical approach: strengthening through grain refinement
(Hall-Petch law)
 technology: grain refinement through severe plastic
deformation (SPD) using continuous extrusion on CONFORM
followed by rotary swaging

8. www.comtesfht.cz
Effect on grain size
8
=200 µm; Map3; Step=0.75 µm; Grid600x500
20 mm
Feedstock
Multiple conformed
Swaging (7 mm)

9. www.comtesfht.cz
CONFORM + rotary swaging of Ti gr. 2
 Rm=1000 Mpa (diameter of 5 mm)
 nanostructured Ti gr. 2 reached mechanical properties of
commercial Ti gr. 4 and Ti gr. 5
0,0
5,0
10,0
15,0
20,0
25,0
30,0
0,0
200,0
400,0
600,0
800,0
1000,0
1200,0
Elongation,A5[%]
Rm[MPa],R0.2[MPa]
True strain, φ [-]
Ti GRADE 2
Rp0,2[Mpa] Rm[Mpa]
ASTM Grade
Tensile
strength
Rm (MPa)
Yield
strength
Rp0.2
(MPa)
Elongation
A5(%)
Grade 1 min. 240 min. 170 24
Grade 2 min. 345 min. 275 20
Grade 3 min. 450 min. 380 18
Grade 4 min. 550 min. 483 15
Grade 5 min. 895 min. 828 10
nano Ti gr. 2 1000 950 12

10. www.comtesfht.cz
CONFORM + rotary swaging of Ti gr. 4
 Rm=1200 MPa
 nanostructured Ti gr. 4 has better mechanical properties than
commercial Ti gr.5
ASTM Grade
Tensile
strength
Rm (MPa)
Yield
strength
Rp0.2 (MPa)
Elongation
A5(%)
Grade 1 min. 240 min. 170 24
Grade 2 min. 345 min. 275 20
Grade 3 min. 450 min. 380 18
Grade 4 min. 550 min. 483 15
Grade 5 min. 895 min. 828 10
nano Ti gr. 2 1000 950 12
nano Ti gr. 4 1210 1190 11
0,0
5,0
10,0
15,0
20,0
25,0
30,0
0,0
200,0
400,0
600,0
800,0
1000,0
1200,0
1400,0
Elongation,A5[%]
Rm[MPa],R0.2[MPa]
True strain, φ [-]
Ti GRADE 4
Rp0,2[Mpa] Rm[Mpa]

11. www.comtesfht.cz
Summary
 Nanostructured titanium is a unique opportunity to
improve mechanical properties of dental implants
(no problems with biocompatibility)
 Since 2013 nanostructured Ti made at COMTES FHT
is used for making of special implants
11

12. www.comtesfht.cz
Thank you for your attention!
12