Construction of metal transfer modes maps for an ER4130 filler metal in GMAW process

Abstract

Metal transfer modes (MTMs) maps were constructed for GMAW process using ER4130 and 98%Ar-2%O2 shielding gas. There is no available MTMs maps for this filler metal which is used to obtain matching strength in welds of AISI 4130/4140 steels. These maps serve as tools to establish the MTM given a welding current and voltage, which is useful when an engineer is trying to qualify welding procedures according to construction codes. The maps were built analyzing current and voltage signals recorded at 5000 samples/second during bead-on-plate welds. The main advantage of this methodology is its simplicity of instrumentation without expensive cameras, but has low resolution and it is difficult to identify finer characteristics of MTMs, such as subgroups (repelled globular, streaming, rotational spray), drop diameter, explosive transfer, etc. Several MTMs were identified in the signal analysis and grouped into natural MTMs (short circuit, globular and spray) and interchangeable modes (short-circuit-globular, globular-spray and short-circuit-globular-spray).

Keywords

• Metal transfer mode (MTM)
• MTM Map
• Amperage Signal
• Voltage Signal
• Stubbing