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Steel 300M vs 4330V

Steel · grade comparison

Steel 300M and 4330V are both steel grades, both aerospace steel. 300M is the stronger of the two: yield strength 760 MPa (110 ksi) against 720 MPa (104 ksi) for 4330V, about 6% more; tensile strength follows at 1,100 MPa (160 ksi) vs 1,000 MPa (145 ksi). In exchange, 4330V is the more ductile: elongation 14% versus 12% for 300M, and 300M is harder (320 HB vs 300 HB). On the shop floor, 4330V welds better (fair vs poor) and 4330V sits in a lower cost tier (standard, $$) than 300M (specialty, $$$$$).

300MChoose it when strength drives the design.

4330VChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

300M vs 4330V: properties

300M4330V

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
205 GPa29.7 Msi

Shear Modulus

78 GPa11.3 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

1,100 MPa160 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

760 MPa110 ksi
720 MPa104 ksi

Elongation at Break

12%
14%

Reduction in Area

45%
40%

Compressive Strength

800 MPa116 ksi
930 MPa135 ksi

Shear Strength

660 MPa95.7 ksi
600 MPa87 ksi

Fatigue Strength (Endurance Limit)

520 MPa75.4 ksi
450 MPa65.3 ksi

Fracture Toughness (K_IC)

95 MPa·√m86.5 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
27 J19.9 ft·lbf

Hardness, Brinell

320 HB
300 HB

Hardness, Rockwell C

34 HRC
31 HRC

Hardness, Vickers

335 HV
315 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.83 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,400°C2,552 °F
1,425°C2,597 °F

Liquidus Temperature

1,470°C2,678 °F
1,495°C2,723 °F

Thermal

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

Thermal Conductivity

40 W/m·K23.1 BTU/hr·ft·°F
43 W/m·K24.8 BTU/hr·ft·°F

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12 µm/m·K6.7 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
270 J/g116 BTU/lb

Same in both: Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -73°C-99 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
7.8 % IACS

Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

12 / 100
15 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V

Manufacturability

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

Machinability

38 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
45%

Weldability

25 / 100
45 / 100

Formability (cold)

18 / 100
28 / 100

Castability

25 / 100
30 / 100

Brazeability / Solderability

25 / 100
55 / 100

Polishability

75 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

40 MJ/kg17,197 BTU/lb
36 MJ/kg15,477 BTU/lb

Embodied Carbon (primary production)

2.8 kg CO₂/kg
2.5 kg CO₂/kg

Typical Recycled Content

20%
25%

Same in both: Embodied Water 70 L/kg8.4 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

140 kN·m/kg
127 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

1,444 kJ/m³
1,264 kJ/m³

Thermal Diffusivity

10.8 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

18
17

Strength versus weight

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

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale300M4330V

Manufacturing and finishing

Capability300M4330V
Default conditionHRHR
Relative cost$$$$$ Specialty$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

300M vs 4330V — frequently asked

Is 300M stronger than 4330V?

Yes. 300M has a typical yield strength of 760 MPa (110 ksi) against 720 MPa (104 ksi) for 4330V — about 6% more. Tensile strength is 1,100 MPa (160 ksi) vs 1,000 MPa (145 ksi).

Which is cheaper, 300M or 4330V?

4330V is the lower-cost material: it sits in the standard tier ($$) while 300M is specialty ($$$$$). 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, 300M or 4330V?

4330V, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for 300M; for welding the order is 4330V first (fair, 45/100) then 300M (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 300M and 4330V 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.