The difference between ER70S-6 and other welding wires of ER70S series
These welding consumables can weld carbon steel and 500Mpa low alloy steel. Is there any difference between ER70S-6 and ER70S-2, ER70S-3, ER70S-4, ER70S-6, ER70S-7?
Chemical composition comparison:ER70S-6 vs ER70S Series
Except for the ER70S-2 welding wire, the main differences of the other welding wires are concentrated on the three elements of C, Mn and Si. The difference of Mn / Si in the welding wire will affect the metallurgical reaction of welding, in addition to affecting the performance of the weld, it will also affect the manufacturability of the welding material.
Impact performance comparison:
ER70S-4 does not require impact toughness. Impact toughness requirement of ER70S-3 is weaker than that of ER70S-2, ER70S-6, ER70S-7.
Comparison of application conditions:
There are more detailed application scenarios of different welding wires in AWS 5.18.
ER70S-2 Welding wire
The ER70S-2 welding wire and filler wire are popular in single-pass welding and some multi-pass welding. Due to the addition of deoxidizers, this filler metal can weld steel with rust and dirt on the surface. But it would decrease the quality of the weld, depending on the surface condition.
ER70S-2 filler metal is widely used for high quality and high toughness welds produced by GTAW (Gas Tungsten Arc Welding) method. These filler metals are also well suited for welding on one side without the need for root gas shielding on the opposite side of the joint.
ER70S-3 Welding wire
ER70S-3 are suitable for welding single and multi-pass welds. Typical base metal standards are generally the same as those applicable to the ER70S-2 category. Wires of the ER70S-3 category are the most widely used GMAW wires classified under this standard.
ER70S-4 Welding wire
ER70S-4 category is suitable for welding steel grades whose conditions require more deoxidation than the ER70S-3 filler metal. Typical base metal standards are generally the same as those applicable to the ER70S-2 category. Impact testing is not necessary for this category.
ER70S-6 Welding wire
ER70S-6 category are suitable for both single-pass and multi-pass welding. They are particularly suitable for sheet metal where a smooth weld bead is necessary.
These wires allow higher current ranges. The shielding gas is CO2 or argon / oxygen mixtures or argon / CO2 mixtures. The base metal typically used is the same as ER70S-2.
ER70S-7 welding wire and filler wire are suitable for single and multi-pass welding. They can weld at higher travel speeds than ER70S-3 filler metal.
At present, what we use mostly is ER70S-6 welding wire. It consumes the most. The second one is ER70S-3. In daily welding job, we seldom use other ER70s series welding wires. ER70S-3 is popular in the automobile industry and construction machinery industries. The ER70S-4 is mainly in less demanding industries such as the bicycle industry.