D55 vs D65
D65 is 1.2 times as stiff as D55. It is 1.1 times as dense. Per unit mass they are about equally stiff (19.62 and 20.56 MJ/kg). Strength: f_m,k = 55 MPa for D55, f_m,k = 65 MPa for D65.
Side by side
ratio = D65 / D55 · log scale| Property | D55 | D65 | Unit | Ratio | ¼×1×4× |
|---|---|---|---|---|---|
| E₁ Modulus, direction 1 | 15.5 | 18.5 | GPa | 1.19× | |
| E₂ Modulus, direction 2 | 1.03 | 1.23 | GPa | 1.19× | |
| E₃ Modulus, direction 3 | 1.03 | 1.23 | GPa | 1.19× | |
| G₁₂ Shear modulus 1-2 | 0.97 | 1.16 | GPa | 1.2× | |
| G₁₃ Shear modulus 1-3 | 0.97 | 1.16 | GPa | 1.2× | |
| E₀,₀₅ Modulus parallel to grain, 5 % fractile | 13 | 15.5 | GPa | 1.19× | |
| ρ Density | 790 | 900 | kg/m³ | 1.14× | |
| ρ_k Density, characteristic (5 % fractile) | 660 | 750 | kg/m³ | 1.14× | |
| f_m,k Bending strength | 55 | 65 | MPa | 1.18× | |
| f_t,0,k Tension parallel to grain | 33 | 39 | MPa | 1.18× | |
| f_t,90,k Tension perpendicular to grain | 0.6 | 0.6 | MPa | 1× | |
| f_c,0,k Compression parallel to grain | 32 | 35 | MPa | 1.09× | |
| f_c,90,k Compression perpendicular to grain | 6.6 | 11.3 | MPa | 1.71× | |
| f_v,k Shear strength | 4.7 | 5 | MPa | 1.06× | |
| E/ρ Specific stiffness E/ρ · derived | 19.62 | 20.56 | MJ/kg | 1.05× | |
| c₀ Bar wave speed √(E/ρ) · derived | 4429 | 4534 | m/s | 1.02× | |
| f/ρ Specific strength f/ρ · derived | 69.62 | 72.22 | kJ/kg | 1.04× |
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.