Abstract:
The incessant occurrence of weld failure in both domestic and industrial structures in Nigeria, resulting from
poorly welded joints, has caused irredeemable losses to humans and properties. To mitigate against these
failures, it is imperative to establish optimum process parameters that can improve mechanical properties of
welded joints. The Step-wise Weight Assessment Ratio Analysis (SWARA) method, a multi-criteria decision
making tool was used to determine the geometric mean of weights for each of the output parameters which
include the mechanical test and weld sample measurement values taken. The Weighted Aggregates Sum
Product Assessment (WASPAS) method is an exceptional blend of weighted sum model (WSM) and
Weighted Product Model (WPM). This method makes use of linear normalization of decision matrix elements
to achieve optimality. In this study, the SWARA-WASPAS method was embraced to assess the outcome of
process parameters on the quality of mild steel welded joints. From applying the SWARA-WASPAS method,
weldments six (6) was selected optimally to possess the best mechanical properties amongst the eight (8)
experimental welded joints analysed, with bead penetration (BP) of 6.35mm, ultimate tensile strength (UTS)
of 450MPa, heat affected zone (HAZ) width of 0.95mm and weld undercut (UC) of 0.05mm. This method
has successfully optimized the mechanical properties of mild steel weldments. |
