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Titanium Grade 1 vs Ti Grade 21

Titanium · grade comparison

Titanium Grade 1 and Ti Grade 21 are both titanium grades. Ti Grade 21 is the stronger of the two: yield strength 805 MPa (117 ksi) against 220 MPa (31.9 ksi) for Grade 1, about 3.7 times as much; tensile strength follows at 830 MPa (120 ksi) vs 300 MPa (43.5 ksi). In exchange, Grade 1 is the more ductile: elongation 30% versus 18% for Ti Grade 21, and Ti Grade 21 is harder (285 HV vs 125 HV). Grade 1 is lighter (4.51 g/cm³ vs 4.94 g/cm³ for Ti Grade 21) and Grade 1 is stiffer (103 GPa vs 79 GPa). On the shop floor, Grade 1 machines more easily (fair vs poor), Grade 1 welds better (excellent vs very good), and Ti Grade 21 sits in a lower cost tier (high, $$$$) than Grade 1 (specialty, $$$$$).

Grade 1Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

Ti Grade 21Choose it when strength drives the design, or when the part sees heat.

Grade 1 vs Ti Grade 21: properties

Grade 1Ti Grade 21

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

103 GPa14.9 Msi
79 GPa11.5 Msi

Shear Modulus

40 GPa5.8 Msi
31 GPa4.5 Msi

Bulk Modulus

110 GPa16 Msi
105 GPa15.2 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

300 MPa43.5 ksi
830 MPa120 ksi

Yield Strength (0.2% offset)

220 MPa31.9 ksi
805 MPa117 ksi

Elongation at Break

30%
18%

Reduction in Area

55%
45%

Compressive Strength

250 MPa36.3 ksi
830 MPa120 ksi

Shear Strength

240 MPa34.8 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

150 MPa21.8 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

80 MPa·√m72.8 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
32 J23.6 ft·lbf

Hardness, Brinell

120 HB
—

Hardness, Rockwell B

70 HRB
—

Hardness, Vickers

125 HV
285 HV

Hardness, Rockwell C

—
28 HRC

Physical

Density and transition temperatures.

Density

4.51 g/cm³0.16 lb/in³
4.94 g/cm³0.18 lb/in³

Melting Point (Solidus)

1,670°C3,038 °F
1,600°C2,912 °F

Liquidus Temperature

1,670°C3,038 °F
1,660°C3,020 °F

Thermal

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

Thermal Conductivity

20 W/m·K11.6 BTU/hr·ft·°F
7.6 W/m·K4.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Latent Heat of Fusion

295 J/g127 BTU/lb
360 J/g155 BTU/lb

Max Service Temperature (continuous)

300°C572 °F
425°C797 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 8.6 µm/m·K4.8 µin/in·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.6 % IACS
1.3 % IACS

Electrical Resistivity

4.8×10⁻⁷ Ω·m18.9 µΩ·in
1.35×10⁻⁶ Ω·m53.1 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.05 V
-0.1 V

Corrosion Resistance

93 / 100
92 / 100

Manufacturability

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

Machinability

42 / 100
20 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
14%

Weldability

90 / 100
75 / 100

Formability (cold)

82 / 100
80 / 100

Castability

35 / 100
30 / 100

Brazeability / Solderability

40 / 100
45 / 100

Same in both: Polishability 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)

42 kg CO₂/kg
48 kg CO₂/kg

Embodied Water

600 L/kg71.9 gal/lb
900 L/kg108 gal/lb

Same in both: Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

67 kN·m/kg
168 kN·m/kg

Specific Stiffness (E / density)

22.8 MN·m/kg
16 MN·m/kg

Modulus of Resilience

235 kJ/m³
4,101 kJ/m³

Thermal Diffusivity

8.5 mm²/s
3.1 mm²/s

Thermal Shock Resistance Index

7
9

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 1Ti Grade 21

Manufacturing and finishing

CapabilityGrade 1Ti Grade 21
CNC machiningYes—
Sheet metalYes—
Default conditionO—
Relative cost$$$$$ Specialty$$$$ High
Min. machined wall1 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Anodizing Type IIYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
CrNYes—
DLCYes—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
TiAlNYes—
TiB2Yes—
TiCNYes—
TiNYes—
WC/CYes—

They share 1 finish: Plasma Spray.

Grade 1 vs Ti Grade 21 — frequently asked

Is Ti Grade 21 stronger than Grade 1?

Yes. Ti Grade 21 has a typical yield strength of 805 MPa (117 ksi) against 220 MPa (31.9 ksi) for Grade 1 — about 3.7 times as much. Tensile strength is 830 MPa (120 ksi) vs 300 MPa (43.5 ksi).

Which is cheaper, Grade 1 or Ti Grade 21?

Ti Grade 21 is the lower-cost material: it sits in the high tier ($$$$) while Grade 1 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, Grade 1 or Ti Grade 21?

Grade 1. Its machinability rates fair (42/100) against poor (20/100) for Ti Grade 21; for welding the order is Grade 1 first (excellent, 90/100) then Ti Grade 21 (very good, 75/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Grade 1 and Ti Grade 21 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.