Technology

Materials

Get informed about the implant materials used at implantcast.

implavit®; CoCrMo

The majority of implants are made of a cobalt chrome molybdenum (CoCrMo) casting alloy (according to ISO 5832-4). Casting molds are produced from reproducible wax models which are, via several steps, coated with a ceramic layer. After the wax has been melted out of these ceramic molds then the liquid CoCrMo alloy is carefully poured inside them. Once this has cooled the ceramic mold is removed from the casting blank and the components are checked for defects. Only then are they machined further and sent for finishing (i.e. ground, polished, coated, etc. – as applicable).

Chemical Composition

element

mass fraction in %

Chromium26.5 to 30
Molybdenum4.5 to 7
Nickel max. 1.0
Ironmax. 1.0
Carbonmax. 0.35
Manganesemax. 1.0
Siliconmax. 1.0
Cobalt~balance

CoCrMo according to ISO 5832-12 is a wrought cobalt-chromium-molybdenum alloy for implants for surgery.

Chemical Composition

elementmass fraction in %
alloy 1 (low carbon cotent)
Chromium
26.0 to 30.0
Molybdenum
5.0 to 7.0
Iron
max. 0.75
Manganese
max. 1.0
Silicon
max. 1.0
Carbon
max. 0.14
Nickel
max. 1.0
Nitrogen
max. 0.25
Cobalt
Rest

 

 

cpTi

cpTi is commercially pure titanium. The unalloyed titanium used in the manufacture of implants for surgery (e.g. AGILON®-components for the shoulder endoprosthetics) complies with ISO 5832-2. The chemical compositions of the titanium grades, which differ in their mechanical properties (e.g. tensile strength), are listed below.

Chemical Composition

element

mass fraction in %

Grade 1 ELIGrade 1Grade 2Grade 3Grade 4A and 4B
Nitrogenmax. 0.012max. 0.03max. 0.03max. 0.05max. 0.05
Carbonmax. 0.03max. 0.08max. 0.08max. 0.08max. 0.08
Hydrogenmax. 0.0125a
max. 0.0125a
max. 0.0125a
max. 0.0125a
max. 0.0125a
Ironmax. 0.10
max. 0.20
max. 0.30
max. 0.30
max. 0.50
Oxygenmax. 0.10max. 0.18max. 0.25max. 0.35max. 0.40
Titaniumremainder
remainder
remainder
remainder
remainder
a Except for blocks for which the maximum hydrogen content shall be 0.0100% (mass fraction) and for flat products for which the maximum hydrogen content shall be 0.015% (mass fraction).

 

 

implatan®; TiAl6V4

The raw titanium (TiAl6V4) alloy material (according to ISO 5832-3) is machined – usually by milling and / or turning before being sent for finishing (i.e. ground, polished, coated, etc. – as applicable)

Chemical Composition

element

mass fraction in %

Aluminium5.5 to 6.75
Vanadium3.5 to 4.5
Ironmax. 0.3
Oxygenmax. 0.2
Carbonmax. 0.08
Nitrogenmax. 0.05
Hydrogen max. 0.015
Titanium~balance

 

 

implatan®; TiAl6Nb7

Titanium Aluminium-6 Niobium-7 (TiAl6Nb7) according to ISO 5832-11 is a wrought titanium alloy used in the manufacture of implants for surgery.

Chemical Composition

element

mass fraction in %

Aluminium5.5 to 6.5
Niobium6.5 to 7.5
Tantalummax. 0.50
Ironmax. 0.25
Oxygenmax. 0.20
Carbonmax. 0.08
Nitrogen max. 0.05
Hydrogenmax. 0.009
Titaniumremainder

 

 

UHMWPE

Ultra high molecular weight polyethylene, or UHMWPE (according to ISO 5834-2), starts out as a powder which is compression molded to make rods. These are then heat-treated and cut into pucks or cubes for stress reduction before product-specific processing. The resultant implants are placed in gas-permeable packaging and sterilised using ethylene oxide (EtO).

implacross®

This is a version of UHMWPE (according to ISO 5834-1) which has been crosslinked to decrease wear rates. The rod material (formed from compression molding GUR 1020 powder) is gamma-irradiated with 75kGy in the atmosphere at room temperature. The rod is then heated to 150°C ± 2°C for 10 hours before being allowed to return to room temperature.

implacross® E

This is a vitamin E stabilised version of the crosslinked implacross® UHMWPE material (hence implacross® E also complies with ISO 5834-1). In this instance however 1000 ppm of vitamin E is thoroughly mixed with the GUR 1020 UHMWPE powder prior to compression molding into plate form. The plate is cross-linked by gamma-irradiation (50 kGy and 75 kGy respectively) before being heat-treated. The use of vitamin E is intended to improve the long-term stability of the UHMWPE by bonding with the free-radicals that may be left behind after the gamma-irradiation or cross-linking steps. The vitamin E which is mixed in at the powder stage has an affinity for these free-radicals and bonds with them before the free-radicals can bond with oxygen (oxidation) which shortens the UHMWPE molecule and damages the mechanical properties of the UHMWPE molecule.

BIOLOX® forte

The BIOLOX® forte hip heads are ceramic hip heads based on the ISO 6474-1 Type A.

Chemical Composition

element

mass fraction in %

Alumina (base material)min. 99.7
Magnesium oxide (sinter additives)max. 0.2
Impurities (SiO2 + CaO + Na2O)max. 0.1

 

 

BIOLOX® delta

The BIOLOX® delta hip heads are ceramic hip heads based on the ISO 6474-2 Type X.

Chemical Composition

element

mass fraction in %

Alumina60 to 90
Zirconia (ZrO2 + HfO2)10 to 30
HfO2 in ZrO2max. 5
Intended additivesmax. 10
Impuritiesmax. 0.2

 

 

Stainless Steel

 

Stainless steel for surgical implants complies with ISO 5832-1.

Chemical Composition

element

mass fraction in %

Carbonmax. 0.030
Siliconmax. 1.0
Manganesemax. 2.0
Phosphorusmax. 0.025
Sulfurmax. 0.010
Nitrogenmax. 0.10
Chromium17.0 to 19.0
Molybdenum2.25 to 3.00
Nickel13.0 to 15.0
Coppermax. 0.50
Ironremainder

Forged high embroidered stainless steel for surgical implants complies with ISO 5832-9.

Chemical Composition

element mass fraction in %
Carbon
max. 0.08
Silicon
max. 0.75
Manganese
2 to 4.25
Nickel
9 to 11
Chromium
19.5 to 22
Molybdenum
2.0 to 3.0
Niobium
0.25 to 0.8
Sulfur
max. 0.01
Phosphorus
max. 0.025
Copper
max. 0.25
Nitrogen
0.25 to 0.5
Iron
remainder
other:
individual max. 0.1
together max. 0.4

Stainless steel for cast and solution-annealed implants comlies with ASTM F 745 for the chemical composition.

Chemical Composition

element mass fraction in %
Carbon
max. 0.06
Silicon
max. 1.0
Manganese
max. 2.0
Nickel
11.00 to 14.50
Chromium
16.50 to 19.00
Molybdenum
2.00 to 3.00
Sulfur
max. 0.030
Phosphorus
max. 0.045
Copper
max. 0.50
Nitrogen
max. 0.20
Iron
balance
Ferrite Content
max. 1

 

 

 

EPORE®

EPORE® is a highly porous structure based on titanium alloy (TiAl6V4). The EPORE® structure is formed by additive manufacturing technology. The additive manufacturing process uses a powder-bed-based method, which is then turned into solid form using an Electron Beam Melting (EBM®).

Further information can be found under the following link:

https://www.implantcast.de/en/company/technology/additive-manufacturing-eporer/

Chemical Composition

element

mass fraction in %

ASTM F 3001ISO 5832-3
Aluminium5.5 to 6.55.5 to 6.75
Vanadium3.5 to 4.53.5 to 4.5
Ironmax. 0.25max. 0.3
Oxygenmax. 0.13max. 0.2
Carbonmax. 0.08max. 0.08
Nitrogenmax. 0.05max. 0.05
Hydrogenmax. 0.012max. 0.015a
Yttriummax. 0.005-
other elements, eachmax. 0.1-
other elements, totalmax. 0.4-
Titaniumremainderremainder
a Excluded are blocks for which the maximum hydrogen content must be 0.010% (mass fraction).

 

 

other materials

  • PET: Polyethyleneterephtalate
  • PEEK: Polyetheretherketone