IM PROVEMENT OF MECHANICAL PROPERTIES OF ALUMINUM ALLOY 6061 –T6 WELD JOINT USING DC PULSED GAS TUNGSTEN ARC WELDING (PGTAW)

الملخص

The effect of DC pulsed GTAW method factors on mechanical properties of Aluminum
alloys 6061–T6 is proves. Throbbed GTAW on the sheet having dimension of (200* 100*
5mm) is implemented at variable pulse current (150, 160, 170, 190) and constant frequency
to get numerous connected joints by electrode type" ER4043 (Al Si5) as a padding metallic
and argon as protective gas and compared with base current GTAW welding at D C current
at 90 amps. The welded pieces are examined by X-ray radiography. The welded joints were
treated by heat, the joints heated for half an hour in the furnace to 150 C° then cooled in the
air to release the residual stresses. Mechanical quality of the weld joints. Microstructural
categorizations, Micro hardness, enduring stress are examined. Consequences exposed that
a common decline of mechanical properties of TIG welded joints conveyed 34% analogies
with parent metal while the PGTAW joined offers better mechanical qualities analogy with
of TIG joined in reductions conveyed 8.4% analogies with original metal this is because of
the microstructure variations through the joining method and compressive residual stress
generation in the weld zones. It has been found that by PGTAW improved the mechanical
properties of welded joints which rely on current parameters.