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Stainless Steel 15-5 PH vs PH14-8Mo

Stainless Steel · grade comparison

Stainless Steel 15-5 PH and PH14-8Mo are both stainless steel grades. 15-5 PH is the stronger of the two: yield strength 795 MPa (115 ksi) against 415 MPa (60.2 ksi) for PH14-8Mo, about 92% more; tensile strength follows at 1,030 MPa (149 ksi) vs 895 MPa (130 ksi). In exchange, PH14-8Mo is the more ductile: elongation 25% versus 14% for 15-5 PH, and 15-5 PH is harder (33 HRC vs 25 HRC). PH14-8Mo runs hotter in service (400°C vs 300°C continuous) and 15-5 PH conducts heat better (17.9 W/m·K vs 15.9 W/m·K). On the shop floor, 15-5 PH welds better (very good vs good) and PH14-8Mo sits in a lower cost tier (high, $$$$) than 15-5 PH (specialty, $$$$$).

15-5 PHChoose it when strength drives the design, or when it will be welded.

PH14-8MoChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

15-5 PH vs PH14-8Mo: properties

15-5 PHPH14-8Mo

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

196 GPa28.4 Msi
200 GPa29 Msi

Bulk Modulus

148 GPa21.5 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.27
0.28

Tensile Strength (Ultimate)

1,030 MPa149 ksi
895 MPa130 ksi

Yield Strength (0.2% offset)

795 MPa115 ksi
415 MPa60.2 ksi

Elongation at Break

14%
25%

Reduction in Area

55%
60%

Compressive Strength

810 MPa117 ksi
—

Shear Strength

640 MPa92.8 ksi
570 MPa82.7 ksi

Fatigue Strength (Endurance Limit)

480 MPa69.6 ksi
380 MPa55.1 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
—

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

311 HB
—

Hardness, Rockwell C

33 HRC
25 HRC

Hardness, Vickers

330 HV
260 HV

Hardness, Rockwell B

—
95 HRB

Same in both: Shear Modulus 77 GPa11.2 Msi

Physical

Density and transition temperatures.

Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,440°C2,624 °F

Thermal

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

Thermal Conductivity

17.9 W/m·K10.3 BTU/hr·ft·°F
15.9 W/m·K9.2 BTU/hr·ft·°F

Specific Heat Capacity

420 J/kg·K0.1 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
11 µm/m·K6.1 µin/in·°F

Max Service Temperature (continuous)

300°C572 °F
400°C752 °F

Min Service Temperature

-73°C-99 °F
-196°C-321 °F

Same in both: Latent Heat of Fusion 270 J/g116 BTU/lb

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.2 % IACS · Electrical Resistivity 8×10⁻⁷ Ω·m31.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.25 V

Corrosion Resistance

57 / 100
62 / 100

Manufacturability

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

Machinability

42 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
40%

Weldability

70 / 100
60 / 100

Formability (cold)

45 / 100
70 / 100

Castability

55 / 100
—

Polishability

80 / 100
75 / 100

Same in both: Brazeability / Solderability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Carbon (primary production)

5.5 kg CO₂/kg
4.6 kg CO₂/kg

Embodied Water

190 L/kg22.8 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

35%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

132 kN·m/kg
115 kN·m/kg

Specific Stiffness (E / density)

25.1 MN·m/kg
25.6 MN·m/kg

Modulus of Resilience

1,612 kJ/m³
431 kJ/m³

Thermal Diffusivity

5.5 mm²/s
4.4 mm²/s

Thermal Shock Resistance Index

9
6

Strength versus weight

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

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scale15-5 PHPH14-8Mo

Manufacturing and finishing

Capability15-5 PHPH14-8Mo
CNC machiningYes—
Sheet metalYes—
3D printingYes—
Default conditionCondition A—
Relative cost$$$$$ Specialty$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
Electropolished (Metal AM)Yes—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

15-5 PH vs PH14-8Mo — frequently asked

Is 15-5 PH stronger than PH14-8Mo?

Yes. 15-5 PH has a typical yield strength of 795 MPa (115 ksi) against 415 MPa (60.2 ksi) for PH14-8Mo — about 92% more. Tensile strength is 1,030 MPa (149 ksi) vs 895 MPa (130 ksi).

Which is cheaper, 15-5 PH or PH14-8Mo?

PH14-8Mo is the lower-cost material: it sits in the high tier ($$$$) while 15-5 PH is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, 15-5 PH or PH14-8Mo?

15-5 PH. Its weldability rates very good (70/100) against good (60/100) for PH14-8Mo.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15-5 PH and PH14-8Mo 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.