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Gas metal arc welding (GMAW) is one of the prime arc welding processes in which an electric
arc is formed between a consumable wire electrode and the metal work piece, which heats the
metal work piece allowing them to join by melting. Significant advancements have been made in
this field in recent years to improve and optimize welding performance with high efficiency and a
higher rate of production. The shielding gas is an essential component of gas shielded welding
processes, its purpose is to shield the weld area from atmospheric gas contamination and provide
a transport medium for the electrical current to flow. It is crucial to determine an ideal composition
of the shielding gas to achieve its effective exploitation and thereby optimization of the process.
A shielding gas mixture composing of two or more gases is commonly used in GMAW to benefit
from the distinguishing abilities of each gas. The shielding gas composition is known to affect
various weld aspects including arc characteristics, metal transfer process, weld appearance,
geometry, and mechanical properties. These factors play a crucial role in determining the weld
quality. In this research, a two-component mixture of the shielding gas is used in GMAW. The
research primarily focuses on evaluating the effect of different mixtures of shielding gases on arc
characteristics including temperature distribution, pressure distribution, flow velocity, current
density, electric potential, and electric field along with a DH-36 steel workpiece considered
through numerical simulation in Ansys CFX. We use different inert and reactive gases to observe
the influence of shielding gases. The effects of pure argon, as well as varying percentages of O2
and CO2 mixed with argon, are observed. The obtained results are analyzed using diverse
properties of the shielding gases including density, viscosity, electrical conductivity, thermal
conductivity, radiative emission coefficient and specific heat. This research is aimed at guiding the
manufacturing industries in utilizing the shielding gases in an optimized way and improve the
overall welding efficiency.