Abstract :
Welding is a metal joining technique by melting some of the base metal and filler
metal with or without pressure and with or without additional metal and generates a
continuous connection. One of the most common and frequently used welding
processes is MIG (metal inert gas) welding which is used for briquette press machine
applications.
This study aimed to identify the effects of welding current on the tensile strength
and microstructure of MIG welding using AWS standard filler in the form of ER70S-6
wire coils. This study employed low carbon steel in terms of AISI 1020 steel. The
material was treated with welding currents of 80 Ampere, 90 Ampere, and 100 Ampere
using MIG welding. The type of seam used is the V seam at an angle of 70°.
The results of the material strength test comparison indicated that the difference
between the current variables of 80 A, 90 A, and 100 A with 5 mm thickness showed a
difference in the tensile strength. The highest tensile strength at the current of 100 A
was 33.346 Kgf/mm² while the lowest tensile strength was at the current of 80 A with
the value of 31.716 Kgf/mm². For testing the microstructure, the greater the current
used in welding, the greater the amount of coarse grain that occurred in the welding
material and would increase the heat input occurred during the welding.