ER70S-3 TIG MIG Welding Wire

ER70S-3 welding wire

ER70S-3 is a mild steel welding wire that is used for general purpose welding. It can be used on mild steel, carbon steel, carbon steel to low alloy steel and cast steel welding applications.

ER70S-3 has similar mechanical properties like ER70S-2 and ER70S-3. The wire can be used for TIG and MIG Welding applications.

ER70S-3 Welding Wire specification

ER70S-3 welding wire specification is AWS A5.18. CWB W48-01 equivalent specification of ER70S-3 is ER49S-3.

ER70S-3 Chemical Composition and Mechanical Properties

ER70S-3 Chemical Composition (AWS A5.18)
Element Range
  Carbon 
0.06- 0.15
  Manganese 0.90 to 1.40
Silicon 0.45 to 0.75
  Phosphorus 0.025% Max.
   Sulfur 0.035% Max.
  Nickel 0.15 Max.
Chromium 0.15 Max.
  Molybdenum 0.15 Max.
  Vanadium 0.03 Max.
  Copper 0.50 Max.
ER70S-3 Mechanical Properties (AWS A5.18)
Properties Value
Tensile Strength, Ksi (MPa) 70, (490) 
Yield Strength, Ksi (MPa)
58 (400)
Elongation, % minimum 22
Toughness 20 ft·lbf at 0°F (27J at-20°C)

ER70S-3 Meaning

ER70S-3 is a low carbon steel welding wire as per AWS A5.18 specification. ER70S-3 is the wire classification number for this TIG & MIG welding wire.

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ER70S-3 welding wire is available in solid form and different diameters.

ER70S-3 Polarity

This welding wire can be used with DCEN and DCEP Polarity. ER70S-3 uses DCEN polarity for TIG welding and DCEP polarity for MIG Welding.

ER70S-3 TIG Rod

ER70S-3 TIG rod is a solid wire that conforms to the AWS A5.18 specification. It is available in different diameters, and it is used for welding mild and low alloy steels.

This type of rod produces excellent welds that are characterized by high strength and low porosity. The arc stability of this rod is also very good, making it an ideal choice for welding in all positions.

ER70S-3 TIG wire is used with pure argon as a welding shielding gas.

ER70S-3 MIG Rod

ER70S-3 MIG Rod, as per AWS A5.18 specification, solid wire, available in different diameters, it can be used with Argon-CO2 mix or 75-25 welding gas.

The ER70S-3 welding rod is a high quality, all-purpose mig welding rod for use with mild steel.

It can be used for welding on both thin and thicker gauge steel. This mig welding rod is especially good for welding on galvanized or zinc coated steel.

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The rod has a low carbon content which makes it less likely to crack during welding.

ER70S-3 vs ER70S-6

Two of the most popular filler metals are ER70S-3 and ER70S-6. But what’s the difference between these two filler metals?

The major differences between ER70S-6 vs ER70S-3 are:

ER70S-3 vs ER70S-6

ER70S-3 ER70S-6
Manganese Level   0.9% to 1.4%  1.45% to 1.85%
 Silicon Level  0.45% to 0.7% Si  0.8% to 1.15%
 Toughness Low (20 ft·lbf @ 0°F) [27J @ –20°C])  High, (20 ft·lbf @ 20°F) [27J @ –30°C]) 
 Welding on rusty materials  Not good for rimmed steel   good for rimmed steel due to high oxidizers
 Mechanical Strength  Low  High due to higher Manganese content
 Welding Shielding Gas  75-25 Welding Gas  75-25 Welding Gas, Pure CO2

Read more: ER70S-3 vs ER70S-6 Wire Compared in depth


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