Steel AISI 1045 vs. Titanium Ti-6Al-4V

Compare Steel AISI 1045 vs. Titanium Ti-6Al-4V strength, stiffness, weight and thermal properties.

Change either side

Mechanical
Try it on a partA bracket to run stress or thermal on, free in your browser	Open in LessCAD	Open in LessCAD
Yield strength	531MPasourceproducer-stated, cold drawn	885MPasourcetypical, plate (>0.187 in), annealed, 0.2% offset
Ultimate tensile strength	627MPasourceproducer-stated, cold drawn	940MPasourcetypical, plate, annealed
Elongation at break	12%sourcein 2 in (50.8 mm)	16%sourcetypical, in 2 in., plate annealed
Young's modulus (stiffness)	210GPasourcetypical	107–122GPasourcetypical range, 20 °C
Density	7,800kg/m³sourcetypical	4,430kg/m³sourcenominal
Strength to weight	68.1kN·m/kg	200kN·m/kg2.93x higher
Stiffness to weight	26.9MN·m/kg4% higher	25.8MN·m/kg
Poisson's ratio	0.3sourcetypical	0.342sourcemean of TIMET measurements
Shear modulus	80.8GPa1.89x stiffer in shear	42.7GPa
Bulk modulus	175GPa	121GPa
Speed of sound	5,189m/s	5,084m/s
Thermal
Thermal conductivity	40–45W/m·Ksourcetypical range, ambient	6.6W/m·Ksourcetypical, 20 °C, mill annealed
Thermal expansion	12µm/m·Ksourcetypical, mean 20-300 °C	9µm/m·Ksourcetypical, mean 0-100 °C
100 mm part over a 50 °C swing	60µm growth	45µm growth33% less
Specific heat	460–480J/kg·Ksourcetypical range, 50/100 °C	580J/kg·Ksourcetypical, 20 °C
Heats up and cools (diffusivity)	11.6mm²/s4.51x faster	2.57mm²/s
Thermal shock resistance	6,269W/m1.68x more resistant	3,730W/m
Melting point	not sourced	1,630–1,650°Csourcemelting range
Max service temperature	not sourced	400°Csourceupper recommended use temperature
Values for	AISI 1045 cold drawn bar (Niagara LaSalle) for mechanical; Ovako C45 (lists 'SAE 1045' as a similar designation) for physical constants	TIMETAL 6-4 (Ti-6Al-4V Grade 5) annealed plate typical (TIMET properties manual) + TIMET datasheet TMC-0150 physical properties

Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Questions

Is Steel AISI 1045 stronger than Titanium Ti-6Al-4V?

Titanium Ti-6Al-4V is stronger: its yield strength is 885 MPa against 531 MPa for Steel AISI 1045 (1.67x).

Which is lighter, Steel AISI 1045 or Titanium Ti-6Al-4V?

Titanium Ti-6Al-4V is lighter: 4,430 kg/m³ against 7,800 kg/m³ for Steel AISI 1045.

Which is stiffer, Steel AISI 1045 or Titanium Ti-6Al-4V?

Steel AISI 1045 is stiffer: Young's modulus 210 GPa against 115 GPa for Titanium Ti-6Al-4V, so the same part in Steel AISI 1045 deflects less under the same load.

Which is lighter for the same job, Steel AISI 1045 or Titanium Ti-6Al-4V?

For the same stiffness or strength: Steel AISI 1045 is lighter for a stiff rod or tie (tension); Titanium Ti-6Al-4V is lighter for a stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.

Part that must be	Steel AISI 1045	Titanium Ti-6Al-4V
Stiff rod or tie (tension)	lighter	4% heavier
Stiff beam (bending)	30% heavier	lighter
Stiff panel or plate	44% heavier	lighter
Strong rod or tie	2.93x heavier	lighter
Strong beam	2.48x heavier	lighter
Strong panel or plate	2.27x heavier	lighter

For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).

Which conducts heat better, Steel AISI 1045 or Titanium Ti-6Al-4V?

Steel AISI 1045 conducts heat better: 42.5 W/m·K against 6.6 W/m·K for Titanium Ti-6Al-4V.

Which expands less with temperature?

Titanium Ti-6Al-4V expands less: 9 µm/m·K against 12 µm/m·K for Steel AISI 1045.

Among 59 materials

Stiffness against density

Strength against density