EFFECT OF CARBIDE PRECIPITATION ON 316L AUSTENITIC STAINLESS STEEL WELDED JOINTS : INVESTIGATING THE METALLURGICAL & TENSILE PROPERTIES

In this study effect of carbide precipitation analyzed on the metallurgical and tensile properties of gas tungsten arc welded austenic stainless steels. The yield strength ultimate tensile strength percentage elongation and metallographic studies are done to evaluate the effect of carbide precipitation. The multi-pass GTAW process is used for the fabrication single V and double V welded butt joint of the stainless steel plates. The tensile shows done on the single V and double V welded joints carbide precipitation does not affect the yield strength and UTS significantly but ductility suffer worse from 12 to 20 % due to the heavy carbide precipitation . The tensile studies also reveal that the Double V weld joint showed better tensile properties as compared to the single V welded butt joints. The micro-structural studies showed that weld metal showed dendritic structure and as the post weld thermal aging was induced the extent of carbide precipitation increases. The micro-hardness studies concluded that BM showed the highest micro-hardness and HAZ showed the least as the post welded micro-hardness values showed decreasing trend due to the carbide precipitation revealed in the micro-structure.