Efecto del nitrogeno y la corriente media pulsada de soldadura en la formacion de grietas de solidificacion en aceros inoxidables AISI 316L

摘要

An analysis of the influence of nitrogen concentration in the weld zone and the pulsed mean welding current in the solidification crack formation is presented in this paper. The AISI 316L austenitic stainless steel was employed as the metal base. The welding was done using CC+ pulsed flux cored arc welding process and AWS E316LT-1 wire type. The tests were conducted using CO_2 shielding gas with four different nitrogen levels (0, 5, 10 and 15%) in order to induce different nitrogen weld metal concentrations. The pulsed mean welding current was varied in three levels and the Transvarestraint tangential strain test was fixed of 5%. The results showed that the solidification cracking decreased as the pulsed mean welding current increase. It was also verified that an increase of the weld zone nitrogen level was associated with a decrease in both the total length of solidification crack and the amount of δ fcrrite.