ER420
Class: ER420
AWS: A5.9
Conforms to Certification: AWS A5.9 | ASME SFA A5.9
Weld Process Used for Mig: (GMAW) and Submerged Arc (SAW)
AWS Chemical Composition Requirements
C = 0.25 – 0.40
Cr = 12.0 – 14.0
Ni = 0.60 max
Mo = 0.75 max
Mn = 0.60 max
Si = 0.50 max
P = 0.03 max
S = 0.03 max
Cu = 0.75 max
Available Sizes |
|
| Diameter X Spool Sizes | Diameter X Coil Sizes |
| .025 x 2#, 10#, 25# | 5/64 x mill coil |
| .030 x 2#, 10#, 25#, 33# | 3/32 x 60# & mill coil |
| .035 x 2#, 10#, 25#, 33# | 1/8 x 60# & mill coil |
| .045 x 2#, 10#, 25#, 33# | 3/16 x 60# & mill coil |
| 1/16 x 10#, 25#, 33# also 60# | 5/32 x 60# & mill coil |
Application
This alloy is often used for surfacing applications which call for superior resistance to abrasion. It requires preheat and inter-pass temperatures of not less than 400ºF, followed by slow cooling. Post weld heat treatment is used to temper the weld deposit.
| Deposited Chemical Composition % (Typical) | ||
| C = 0.29 | Mo = 0.10 | P = 0.014 |
| Cr = 13.5 | Mn = 0.45 | S = 0.008 |
| Ni = 25 | Si = 0.48 | |
| Mechanical Properties (R.T.) | |
| Yield Strength | 120,000psi |
| Tensile Strength | 145,000psi |
| Elongation | 45% |
Deposited All Weld Metal Properties
Data is typical for ER420 weld metal deposited by Mig using Argon + 2% oxygen as the shielding gas. Data on sub-arc is not presented, as sub-arc is dependent on the type of flux used.
Note: Mechanical properties are greatly influenced by changes in welding parameters such as preheat and inter-pass temperatures.
Recommended Welding Parameters |
||||||
| GMAW “Mig Process” | Reversed Polarity | |||||
| Wire Diameter | Wire Feed | Amps | Volts | Shielding Gas | Gas CFH | |
| Short Arc Welding | .030 | 13-26 | 40-120 | 16-20 | Argon+2% O2 | 25 |
| .035 | 13-26 | 60-140 | 16-22 | Argon+2% O2 | 25 | |
| Spray Arc Welding | .035 | 20-39 | 140-220 | 24-29 | Argon+2% O2 | 38 |
| .045 | 16-30 | 160-260 | 25-30 | Argon+2% O2 | 38 | |
| 1/16 | 10-16 | 230-350 | 27-31 | Argon+2% O2 | 38 | |
Other shielding Gases may be used for Mig welding. Shielding gases are chosen taking Quality, Cost, and Operability into consideration
Recommended Welding Parameters |
||
| SAW “Submerged Arc Welding Process” | Reversed Polarity Suggested | |
| Wire Diameter | Amps | Volts |
| 3/32 | 250-450 | 28-32 |
| 1/8 | 300-500 | 29-34 |
| 5/32 | 400-600 | 30-35 |
| 3/16 | 500-700 | 30-35 |
Both Agglomerated and fused fluxes can be used for submerged arc welding.
Note: The chemical composition of the flux mainly affects the chemistry of the weld metal and consequently its corrosion resistance and Mechanical properties.