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

Abstract

The effect of DC pulsed GTAW method factors on mechanical properties of Aluminumalloys 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 frequencyto get numerous connected joints by electrode type" ER4043 (Al Si5) as a padding metallicand argon as protective gas and compared with base current GTAW welding at D C currentat 90 amps. The welded pieces are examined by X-ray radiography. The welded joints weretreated by heat, the joints heated for half an hour in the furnace to 150 C° then cooled in theair to release the residual stresses. Mechanical quality of the weld joints. Microstructuralcategorizations, Micro hardness, enduring stress are examined. Consequences exposed thata common decline of mechanical properties of TIG welded joints conveyed 34% analogieswith parent metal while the PGTAW joined offers better mechanical qualities analogy withof TIG joined in reductions conveyed 8.4% analogies with original metal this is because ofthe microstructure variations through the joining method and compressive residual stressgeneration in the weld zones. It has been found that by PGTAW improved the mechanicalproperties of welded joints which rely on current parameters.