D40 vs D75

D75 is 1.7 times as stiff as D40. It is 1.5 times as dense. Per unit mass D75 is 1.1 times as stiff. Strength: f_m,k = 40 MPa for D40, f_m,k = 75 MPa for D75.

D40 EN 338:2016 D75 EN 338:2016

Side by side

ratio = D75 / D40 · log scale

Property	D40	D75	Unit	Ratio
E₁ Modulus, direction 1	13	22	GPa	1.69×
E₂ Modulus, direction 2	0.87	1.47	GPa	1.69×
E₃ Modulus, direction 3	0.87	1.47	GPa	1.69×
G₁₂ Shear modulus 1-2	0.81	1.38	GPa	1.7×
G₁₃ Shear modulus 1-3	0.81	1.38	GPa	1.7×
E₀,₀₅ Modulus parallel to grain, 5 % fractile	10.9	18.5	GPa	1.7×
ρ Density	660	1020	kg/m³	1.55×
ρ_k Density, characteristic (5 % fractile)	550	850	kg/m³	1.55×
f_m,k Bending strength	40	75	MPa	1.88×
f_t,0,k Tension parallel to grain	24	45	MPa	1.88×
f_t,90,k Tension perpendicular to grain	0.6	0.6	MPa	1×
f_c,0,k Compression parallel to grain	27	37	MPa	1.37×
f_c,90,k Compression perpendicular to grain	5.5	12.8	MPa	2.33×
f_v,k Shear strength	4.2	5	MPa	1.19×
E/ρ Specific stiffness E/ρ · derived	19.7	21.57	MJ/kg	1.1×
c₀ Bar wave speed √(E/ρ) · derived	4438	4644	m/s	1.05×
f/ρ Specific strength f/ρ · derived	60.61	73.53	kJ/kg	1.21×

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.