D18 vs D27
D27 is 1.1 times as stiff as D18. It is 1.1 times as dense. Per unit mass they are about equally stiff (16.67 and 17.21 MJ/kg). Strength: f_m,k = 18 MPa for D18, f_m,k = 27 MPa for D27.
Side by side
ratio = D27 / D18 · log scale| Property | D18 | D27 | Unit | Ratio | ¼×1×4× |
|---|---|---|---|---|---|
| E₁ Modulus, direction 1 | 9.5 | 10.5 | GPa | 1.11× | |
| E₂ Modulus, direction 2 | 0.63 | 0.7 | GPa | 1.11× | |
| E₃ Modulus, direction 3 | 0.63 | 0.7 | GPa | 1.11× | |
| G₁₂ Shear modulus 1-2 | 0.59 | 0.66 | GPa | 1.12× | |
| G₁₃ Shear modulus 1-3 | 0.59 | 0.66 | GPa | 1.12× | |
| E₀,₀₅ Modulus parallel to grain, 5 % fractile | 8 | 8.8 | GPa | 1.1× | |
| ρ Density | 570 | 610 | kg/m³ | 1.07× | |
| ρ_k Density, characteristic (5 % fractile) | 475 | 510 | kg/m³ | 1.07× | |
| f_m,k Bending strength | 18 | 27 | MPa | 1.5× | |
| f_t,0,k Tension parallel to grain | 11 | 16 | MPa | 1.45× | |
| f_t,90,k Tension perpendicular to grain | 0.6 | 0.6 | MPa | 1× | |
| f_c,0,k Compression parallel to grain | 18 | 22 | MPa | 1.22× | |
| f_c,90,k Compression perpendicular to grain | 4.8 | 5.1 | MPa | 1.06× | |
| f_v,k Shear strength | 3.5 | 3.8 | MPa | 1.09× | |
| E/ρ Specific stiffness E/ρ · derived | 16.67 | 17.21 | MJ/kg | 1.03× | |
| c₀ Bar wave speed √(E/ρ) · derived | 4082 | 4149 | m/s | 1.02× | |
| f/ρ Specific strength f/ρ · derived | 31.58 | 44.26 | kJ/kg | 1.4× |
Values at the first thickness band or product form of each material (EN 338:2016; EN 338:2016). A minimum and a characteristic value are not the same kind of number — read the ratio as a guide. Each material's page lists every band and every source.