Properties
General information
Overview
Calcium phosphate bio-ceramics are used for scaffolds for bone metabolism and cartilage regeneration. Bone metabolism involves the resorption of existing bone by osteoclasts and the subsequent formation of a new bone matrix by osteoblasts. These are essential for bone remodeling, regeneration and repair. Tissue engineering requires a scaffold capable of supporting the functional properties of osteogenic cells.
Composition overview
Compositional summary
Trilcalcium phosphate Ca3(PO4)2, tetracalcium phosphate Ca4P2O9 and hydroxyapatite Ca10(PO4)6(OH)2 are three calcium phosphates used as implant scaffold materials. The data below are for dense (<3% porosity) hydroxyapatite.
|
Material family |
Ceramic (technical) |
|
Base material |
Other |
Composition detail (metals, ceramics and glasses)
|
CaO (calcia) |
55 |
- |
59 % |
|
Other oxide |
41 |
- |
43 % |
|
Other |
0 |
- |
2 % |
Price
|
Price |
* |
132 |
- |
331 |
CNY/kg |
|
Price per unit volume |
* |
4.04e5 |
- |
1.04e6 |
CNY/m^3 |
Physical properties
|
Density |
3.05e3 |
- |
3.15e3 |
kg/m^3 |
Mechanical properties
|
Young's modulus |
55 |
- |
88 |
GPa |
|
|
Specific stiffness |
17.7 |
- |
28.4 |
MN.m/kg |
|
|
Yield strength (elastic limit) |
* |
28 |
- |
48 |
MPa |
|
Tensile strength |
38 |
- |
48 |
MPa |
|
|
Specific strength |
* |
9.03 |
- |
15.5 |
kN.m/kg |
|
Elongation |
* |
0.04 |
- |
0.09 |
% strain |
|
Compressive modulus |
* |
55 |
- |
88 |
GPa |
|
Compressive strength |
* |
350 |
- |
450 |
MPa |
|
Flexural modulus |
|
100 |
- |
120 |
GPa |
|
Flexural strength (modulus of rupture) |
* |
38 |
- |
48 |
MPa |
|
Shear modulus |
* |
21 |
- |
33 |
GPa |
|
Bulk modulus |
* |
55 |
- |
88 |
GPa |
|
Poisson's ratio |
* |
0.3 |
- |
0.33 |
|
|
Shape factor |
15 |
||||
|
Hardness - Vickers |
|
420 |
- |
450 |
HV |
|
Elastic stored energy (springs) |
* |
5.77 |
- |
16.2 |
kJ/m^3 |
|
Fatigue strength at 10^7 cycles |
* |
15.2 |
- |
19.2 |
MPa |
Impact & fracture properties
|
Fracture toughness |
1 |
- |
1.3 |
MPa.m^0.5 |
|
Toughness (G) |
0.0135 |
- |
0.0259 |
kJ/m^2 |
Thermal properties
|
Thermal conductivity |
|
1.2 |
- |
3 |
W/m.°C |
|
Specific heat capacity |
|
870 |
- |
890 |
J/kg.°C |
|
Thermal expansion coefficient |
|
11.4 |
- |
14 |
μstrain/°C |
|
Thermal shock resistance |
* |
29.3 |
- |
59.3 |
°C |
|
Thermal distortion resistance |
* |
0.0944 |
- |
0.239 |
MW/m |
Magnetic properties
|
Magnetic type |
Non-magnetic |
Optical, aesthetic and acoustic properties
|
Transparency |
Opaque |
||||
|
Acoustic velocity |
|
4.18e3 |
- |
5.37e3 |
m/s |
|
Mechanical loss coefficient (tan delta) |
* |
0.00175 |
- |
0.0024 |
|
Critical materials risk
|
Contains >5wt% critical elements? |
No |
Durability
|
Water (fresh) |
Excellent |
|
Water (salt) |
Excellent |
|
Weak acids |
Excellent |
|
Strong acids |
Acceptable |
|
Weak alkalis |
Acceptable |
|
Strong alkalis |
Unacceptable |
|
Organic solvents |
Excellent |
|
Oxidation at 500C |
Excellent |
|
UV radiation (sunlight) |
Excellent |
|
Flammability |
Non-flammable |
Primary production energy, CO2 and water
|
Embodied energy, primary production |
* 102 - 113 MJ/kg |
|
CO2 footprint, primary production |
* 5.51 - 6.09 kg/kg |
|
Water usage |
* 107 - 119 l/kg |
Processing energy, CO2 footprint & water
|
Grinding energy (per unit wt removed) |
* |
24.8 |
- |
27.4 |
MJ/kg |
|
Grinding CO2 (per unit wt removed) |
* |
1.86 |
- |
2.06 |
kg/kg |
Recycling and end of life
|
Recycle |
No |
|
Recycle fraction in current supply |
0.1 % |
|
Downcycle |
Yes |
|
Combust for energy recovery |
No |
|
Landfill |
Yes |
|
Biodegrade |
No |