WELDING METHOD FOR ALUMINUM MATERIAL IMPROVED IN WELD CRACK

摘要

PURPOSE: To prevent a fine crack on a heat-afected zone of weld by controlling the width of a cleaning area to the specified length. ;CONSTITUTION: When a pulse current to change over the polarity of a TIG welding electrode and Al material 1 to the positive and negative is impressed, the cleaning widths W can be regulated within 3mm from deposited metal part toes 3a by setting an EN ratio to about 70-95%. Consequently, stress generated based on imbalance of structure in the solidification process of the heat- affected zone and a deposited metal part 3 is minimized. In addition, since bubbles and foreign matters are mixed at the time of welding and defective appearance is caused when the cleaning width is diminished to zero, the cleaning width is preferably regulated to 0.1-1mm.;COPYRIGHT: (C)1993,JPO&Japio