Characterization and Parametric Optimization of EN-10149-2 Steel Welded Joints Made by MIG Welding

Abstract

Welding Is One Of The Secondary Manufacturing Methods, For Joining Similar Or Dissimilar Materials With Different Joint Configurations Using Various Materials. There Are Many Welding Processes Existed To Join The Metals, In Which Mig Welding Is One Of The Most Widely Used Processes In Industries To Weld Materials Thickness From 2mm To 12mm Sheet And Plate Respectively. The Mig Welding Process Has Many Process Parameters Which Are Responsible For The Productivity, Quality And Cost Of Welded Joints. Advanced High Strength Steels (Ahss) Are Multiphase Steels That Contain Various Concentrations Of Ferrite, Bainite, Martensite And Retained Austenite Phases. The Unique Physical Characteristics Of Ahss Present Some Challenges To Welding And Bonding Processes. Ahss Has Tendency To Change Micro-Structure And Mechanical Properties By Any Welding Process Like Other Steels. Based On The Significant Applications In Various Industries, The Experimental Works Are Carried Out On One Of Ahss Materials En-10149-2 S700mc Of Thickness 2mm Steel Sheet Metal By Mig Welding Process Parameters Such As (Current, Voltage, Welding Speed). For All Combinations Of Process Parameters, The Butt Joints Are Fabricated. The Butt Joints Are Inspected Through Different Non-Destructive Testing For Defects Detection. All The Defect Free Joints Are Characterized Through Micro-Structure (At Different Zones Of Joint), Hardness And Tensile Tests. The Analysis From Doe Method Used To Identify Which Parameter Is The Most Significant Among All Parameters. Confirmatory Test Was Also Done By Taking The Optimal Parameters And The Results Show That The Improvement Of The Response Variables WasAcceptable And The Method That Was Used To Optimize Was Valid. Finally, By Using Optimum Parameters In-Terms Of Current, Voltage And Welding Speed The Tensile Strength WasIncreased From 765mpa To 780mpa, The Hardness Of Weld Zone Was Increased From 150vhn To 157vhn And The Hardness Of Haz Increased From 145.1 Vhn To 166.47 Vhn.