ABSTRACT
Globular oxide acts as a starting point of hydrogen gas pressure in welding joints, fine cracks produced at the oxide can weaken the mechanical properties eventually make the specimens brittle and prone to fracture. Experimental results show that the presence of globular oxides on the fracture surface of weldment for the specimen be charged with hydrogen showed that the hydrogen embrittlement phenomenon has a significant influence on the mechanical properties of austenitic stainless steels. Hydrogen can enter the weldment from the parent metal being welded, filler metals and the environment. Based on the observations of as-received (AR) specimen, the microstructure of AISI 304 stainless steel has a single phase austenitic structure because no traces of carbides precipitate microstructures found at grain boundaries. A copper strip was placed below the joint to avoid accidental welding onto the workbench. The plates were welded in a flat position by single pass using robotic Gas Metal Arc Welding (GMAW) machine model OTC DR-4000.
