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.