ER420

Class: ER420
AWS: A5.9

Conforms to Certification: AWS A5.9 | ASME SFA A5.9

Weld Process Used for Tig: (GTAW)

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
.030 x 36
.035 x 36
.045 x 36
1/16 x 36
3/32 x 36
1/8 x 36
3/16 x 36
5/32 x 36

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 Tig using 100% Argon as the shielding gas.
Note: Mechanical properties are greatly influenced by changes in welding parameters such as preheat and inter-pass temperatures.

Recommended Welding Parameters

GTAW “Tig Process”
Wire Diameter Amps DCSP Volts Shielding Gas
.035 60-90 12-15 Argon 100%
.045 80-110 13-16 Argon 100%
1/16 90-130 14-16 Argon 100%
3/32 120-175 15-20 Argon 100%

Note: Parameters for tig welding are dependent upon plate thickness and welding position.
Other shielding Gases may be used for Tig welding. Shielding gases are chosen taking Quality, Cost, and Operability into consideration.