FabDigitFabDigit

Titanium Grade 2 vs Grade 4

Titanium · grade comparison

Titanium Grade 2 and Grade 4 are both titanium grades, both corrosion resistant ti. Grade 4 is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 380 MPa (55.1 ksi) for Grade 2, about 45% more; tensile strength follows at 620 MPa (89.9 ksi) vs 440 MPa (63.8 ksi). In exchange, Grade 2 is the more ductile: elongation 28% versus 20% for Grade 4, and Grade 4 is harder (253 HB vs 150 HB). On the shop floor, Grade 2 machines more easily (fair vs poor) and Grade 2 welds better (excellent vs very good).

Grade 2Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

Grade 4Choose it when strength drives the design.

Grade 2 vs Grade 4: properties

Grade 2Grade 4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

103 GPa14.9 Msi
105 GPa15.2 Msi

Tensile Strength (Ultimate)

440 MPa63.8 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

380 MPa55.1 ksi
550 MPa79.8 ksi

Elongation at Break

28%
20%

Reduction in Area

50%
40%

Compressive Strength

440 MPa63.8 ksi
570 MPa82.7 ksi

Shear Strength

320 MPa46.4 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

240 MPa34.8 ksi
340 MPa49.3 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
66 MPa·√m60.1 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
22 J16.2 ft·lbf

Hardness, Brinell

150 HB
253 HB

Hardness, Rockwell B

80 HRB
100 HRB

Hardness, Vickers

160 HV
265 HV

Same in both: Shear Modulus 45 GPa6.5 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,665°C3,029 °F
1,660°C3,020 °F

Liquidus Temperature

1,670°C3,038 °F
1,665°C3,029 °F

Same in both: Density 4.51 g/cm³0.16 lb/in³

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

16.4 W/m·K9.5 BTU/hr·ft·°F
17.2 W/m·K9.9 BTU/hr·ft·°F

Specific Heat Capacity

523 J/kg·K0.12 BTU/lb·°F
540 J/kg·K0.13 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

8.6 µm/m·K4.8 µin/in·°F
9 µm/m·K5 µin/in·°F

Min Service Temperature

-250°C-418 °F
-196°C-321 °F

Same in both: Latent Heat of Fusion 365 J/g157 BTU/lb · Max Service Temperature (continuous) 300°C572 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.1 % IACS
2.9 % IACS

Electrical Resistivity

5.6×10⁻⁷ Ω·m22 µΩ·in
6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

93 / 100
92 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

40 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
25%

Weldability

90 / 100
80 / 100

Formability (cold)

78 / 100
50 / 100

Castability

45 / 100
30 / 100

Brazeability / Solderability

35 / 100
40 / 100

Polishability

75 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

650 MJ/kg279,450 BTU/lb
700 MJ/kg300,946 BTU/lb

Embodied Carbon (primary production)

38 kg CO₂/kg
45 kg CO₂/kg

Embodied Water

500 L/kg59.9 gal/lb
800 L/kg95.9 gal/lb

Same in both: Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

98 kN·m/kg
137 kN·m/kg

Specific Stiffness (E / density)

22.8 MN·m/kg
23.3 MN·m/kg

Modulus of Resilience

701 kJ/m³
1,440 kJ/m³

Thermal Diffusivity

7 mm²/s
7.1 mm²/s

Thermal Shock Resistance Index

8
11

Strength versus weight

Yield strength against density for every titanium grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0004.555.5Density (g/cm³)Yield strength (MPa) — log scaleGrade 2Grade 4

Manufacturing and finishing

CapabilityGrade 2Grade 4
Default conditionOO
Relative cost$$$$$ Specialty$$$$$ Specialty
Min. machined wall1 mm1 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 20 finishes: AlCrN, AlTiN, Anodizing Type II, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, CrN, DLC, Electropolishing, HVOF Coating, MoS2 and 8 more.

Grade 2 vs Grade 4 — frequently asked

Is Grade 4 stronger than Grade 2?

Yes. Grade 4 has a typical yield strength of 550 MPa (79.8 ksi) against 380 MPa (55.1 ksi) for Grade 2 — about 45% more. Tensile strength is 620 MPa (89.9 ksi) vs 440 MPa (63.8 ksi).

Which is cheaper, Grade 2 or Grade 4?

Both sit in the same relative cost tier ($$$$$, specialty); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, Grade 2 or Grade 4?

Grade 2. Its machinability rates fair (40/100) against poor (30/100) for Grade 4; for welding the order is Grade 2 first (excellent, 90/100) then Grade 4 (very good, 80/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Grade 2 and Grade 4 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.