Effect of Welding Process to the Porosity Formation in as Welded Carbon Steel

Welding is principle industrial process used for joining metal and it is the versatilemethod that widely used due to its high productivity and relatively low cost in the manufacturing industry. Carbon steel is the most popular material used in large scale in industries due to abundance source, low cost and variety of mechanical properties. The aim of this study is to identify the effect of different welding process to the porosity formation on the weld bead. 3 different types of welding process were used which are MIG welding, MAG welding and TIG welding. SPCC is the type of carbon steel that were used for this research. For samples measurement in MIG welding and MAG welding have same measurement which 180 mm x 100 mm x 5 while TIG welding use different measurement which 100 mm x 75 mm x 3 mm. For characterisation process, X ray industry were used to identify the porosity using visual evaluation. Size of porosity and number of porosity were measured and being recorded. MAG welding shows the biggest size of porosity (1.7 mm) followed by MIG welding (1.5 mm) and TIG welding (1.4 mm). Value of heat input also calculated and TIG shows the highest heat input which 2.94 kJ/mm among other welding process. In observation depth of penetration, TIG welding also shows the deepest penetration than MIG welding and MAG welding. This happen because during TIG welding process, size of sample is thinner than sample MIG welding and MAG welding. Also relate with heat input of TIG is higher.