Study of the Incorporation of Black Sands in the Flux of Submerged Arc Welds of High Strength Low Alloy Steel on Mechanical Properties and Microstructure
摘要
This experimental study establishes the variation of mechanical properties of weld metal of ASTM A572 steel by submerged arc welding (SAW) process when a concentration of raw ferruginous sand is incorporated to neutral flux in weight ratios between 0.1 and 0.3. The microstructure of weld metal samples is evaluated by optical microscopy, and chemical composition analysis is performed by spark Atomic Emission Spectroscopy (spark-AES). The microhardness of weld metal and the tensile strength of the welded joints have been evaluated. The results show that the amount of manganese and silicon is reduced when the sand content increases, leading to the formation of ferritic structures and restricting the formation of acicular ferrite. The microhardness is reduced by 24%, and a reduction in tensile strength is also verified. The reduction in the mechanical response has been attributed to the change in the microstructure evolution of the weld metal.