AWS E308Mo (W30820) Weld Metal
AWS E308Mo is a weld metal formulated for joining stainless steels. Cited properties are appropriate for the as-welded condition. E308Mo is the AWS designation for this material. W30820 is the UNS number. Additionally, the ISO numeric designation is ES308Mo.
It has a fairly high ductility among stainless steel welding fillers. In addition, it has a moderately low electrical conductivity and a moderately low base cost.
The graph bars on the material properties cards below compare AWS E308Mo to: stainless steel welding fillers (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
40 %
Poisson's Ratio
0.28
Shear Modulus
78 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
620 MPa 89 x 103 psi
Thermal Properties
Latent Heat of Fusion
290 J/g
Melting Completion (Liquidus)
1440 °C 2620 °F
Melting Onset (Solidus)
1400 °C 2540 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
16 W/m-K 9.0 BTU/h-ft-°F
Thermal Expansion
14 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.3 % IACS
Otherwise Unclassified Properties
Base Metal Price
19 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
3.8 kg CO2/kg material
Embodied Energy
53 MJ/kg 23 x 103 BTU/lb
Embodied Water
160 L/kg 19 gal/lb
Common Calculations
PREN (Pitting Resistance)
28
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
22 points
Strength to Weight: Bending
20 points
Thermal Diffusivity
4.2 mm2/s
Thermal Shock Resistance
16 points
Alloy Composition
| Fe | 59.6 to 70.5 | |
| Cr | 18 to 21 | |
| Ni | 9.0 to 12 | |
| Mo | 2.0 to 3.0 | |
| Mn | 0.5 to 2.5 | |
| Si | 0 to 1.0 | |
| Cu | 0 to 0.75 | |
| C | 0 to 0.080 | |
| P | 0 to 0.040 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
AWS A5.4: Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding
Welding Metallurgy and Weldability of Stainless Steels, John C. Lippold and Damian J. Kotecki, 2005
Welding Metallurgy of Stainless Steels, Erich Folkhard et al., 2012