CONTROL OF GRAIN COARSENING IN HEAT 1FECTED ZONE BY VARYING THE ANGLE OF ATTACK TO THE WORKPIECE UNDER WELDING

Abstract

In the present Investigation, a work has been carried out to study effect of angle of attack and distance between electrode and weld groove edge in a multipass 108 mm thick plate welding using submerged are welding process. Weld metal were deposited in the grooves plates using 3 mm diameter LS2--Electrode and F-90 green neutral flux. The effect of angle of attack and distance between filler wire and weld groove edge was studied on the width of the HAZ, Grain Coarsening in HAZ and hardness of HAZ. It was found that the width of HA7 increases as angle of attack increases an, decreases as the distance between filler wire and weld groove edge increases. A same pattern is observed for variation in grain size in Hi,Z with the increase of angle of attack and decrc se of c'~.stance between. filler wire and weld groove edge. The hardness of HAZ increases by increasing angle of attack from 50 to 100. By further increasing the angle of attack from 15 to 30° a significant decrease in hardness was observed after that almost constant hardness was observed upto an angle of attack equal to 45°. It is also found that hardness increases as distance between filler wire and weld groove edge increases from 0.4 mm upto 5 mm for the angles