EFFECTS OF POROSITY ON THE FACTURE TOUGHNESS OF 5083@ 5456@ AND 6061 ALUMINUM ALLOY WELDMENTS (To Purchase Call 1-800-854-7179 USA/Canada or 303-397-7956 Worldwide)
Dynamic Tear and J-integral specimens having four levels of porosity were prepared from weldable aluminum alloy welds (5083/5183@6061/5356@ and 5455/5556). All specimens were fatigue precracked before testing. The amount of porosity was measured directly on the fracture surfaces using quantative metallographic methods and was divided into macro- and micro-porosity (pores equal to or larger than and smaller than 0.01-in.@ respectively). Radiography indicates only the macro-porosity as discrete pores. In general@ there was 5 to 10 times more micro-porosity than macro-porosity found on the fracture surfaces. Total porosity was the sum of the macro- and the micro-porosity.