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Welding is a versitile process of metal fabrication that fuses two of more materials for
joining. The choice of welding parameters is a crutial element in planning stage for
producing quality joints. Tungsten Inert Gas (TIG) welding is a high precision welding
technique that uses a non-consumable tungsten electrode in the presence of shielding gas
to produce clean welds. The TIG welding is applicable on variety of metal alloys due to its
controlled parameters ability. The paramount work of this research was to investigate the
TIG welding of distinct stainless-steel grades austenitic stainless steel AISI 304 and Ferritic
Chromium Stainless Steel AISI 430, and analyze the impact of providing distinct nature of
filler materials with controlled welding parameters. The TIG welding is inflenced by
extensive input parameters like welding current, weld speed, arc voltage, shielding gas
flow rate, temperature, and presence of filler material. Preformance impacting factors used
for this study are welding current, filler diameter and shielding Gas flow rate. A
comparative analysis of two different filler materials ER308L and ER410 is produced.
ER308L filler wire produces good mechanical properties when welding disticts metals with
the AISI 304 and AISI 316 due to its strong austenitic weld pool. The utility of ER410 filler
rod in welding AISI 430 material gives strong mechanical leverage over ER308L filler. To
test the mechanical behaviour of AISI 304 and AISI430 welded joint, the experiment is
devided into two sections of ER308L and AISI430 filler based welds. Each set of
experiments were designed using Taguchi L9 DOE orthognal array. The depedency of
mechanical properties, tensile strength, flexural strength and microsctructural hardness was
evaluated using analysis of verience (ANOVA) method. Universal Testing Machine (UTM)
machine was used in conducting tensile and three point bend tests for each sample
produced on fiber laser cutting machine. Rockwell hardness tests (RHT) were conducted
according to ASTM E18 on B00IW5LTBY Gowegroup Rockwell hardness apparatus. The
Optical microscope was utilized for visual analysis of fusion zone, BM and HAZ of each
sample. Tensile tested samples were analyzed under electron microscope for observation
of defect like porosity, penetration of weld, micro cracks, and fusion of metals.