FabDigitFabDigit

Titanium OT4-AW vs OT4-M

Titanium · OT4 temper comparison

OT4-AW and OT4-M are two conditions of the same titanium grade, OT4: AW (as-welded deposit) versus M (thermomechanically controlled processed). The chemistry is identical, so every difference below comes from the condition. Both yield at about 640 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (as-welded deposit versus thermomechanically controlled processed). OT4-M is the more ductile: elongation 16% versus 9% for OT4-AW. OT4-M runs hotter in service (350°C vs 300°C continuous).

OT4-MChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

OT4-AW vs OT4-M: properties

OT4-AWOT4-M

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
780 MPa113 ksi

Elongation at Break

9%
16%

Reduction in Area

20%
35%

Compressive Strength

680 MPa98.6 ksi
690 MPa100 ksi

Shear Strength

460 MPa66.7 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

50 MPa·√m45.5 ksi·√in
65 MPa·√m59.2 ksi·√in

Charpy V-Notch Impact (RT)

28 J20.7 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

250 HB
240 HB

Hardness, Rockwell B

101 HRB
100 HRB

Hardness, Rockwell C

23 HRC
22 HRC

Hardness, Vickers

262 HV
250 HV

Same in both: Elastic (Young's) Modulus 115 GPa16.7 Msi · Shear Modulus 43 GPa6.2 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.32 · Yield Strength (0.2% offset) 640 MPa92.8 ksi

Physical

Density and transition temperatures.

Same in both: Density 4.55 g/cm³0.16 lb/in³ · Melting Point (Solidus) 1,620°C2,948 °F · Liquidus Temperature 1,665°C3,029 °F

Thermal

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

Max Service Temperature (continuous)

300°C572 °F
350°C662 °F

Same in both: Thermal Conductivity 9.5 W/m·K5.5 BTU/hr·ft·°F · Specific Heat Capacity 540 J/kg·K0.13 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 8.6 µm/m·K4.8 µin/in·°F · Latent Heat of Fusion 365 J/g157 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 1.1 % IACS · Electrical Resistivity 1.55×10⁻⁶ Ω·m61 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

85 / 100
88 / 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

26 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

23%
25%

Weldability

65 / 100
72 / 100

Formability (cold)

30 / 100
55 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 620 MJ/kg266,552 BTU/lb · Embodied Carbon (primary production) 38 kg CO₂/kg · Embodied Water 400 L/kg47.9 gal/lb · Typical Recycled Content 25%

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 scaleOT4

OT4-AW vs OT4-M — frequently asked

What is the difference between OT4-AW and OT4-M?

OT4-AW and OT4-M are two conditions of the same titanium grade, OT4: AW (as-welded deposit) versus M (thermomechanically controlled processed). The chemistry is identical, so every difference below comes from the condition. Both yield at about 640 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (as-welded deposit versus thermomechanically controlled processed).

Which condition does FabDigit quote by default, AW or M?

M is the default OT4 condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which welds better, OT4-AW or OT4-M?

OT4-M. Its weldability rates very good (72/100) against good (65/100) for OT4-AW.

Ready to make it?

Upload a CAD file and FabDigit prices the part in OT4-AW and OT4-M 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.