Page 222 - Welding of Aluminium and its Alloys
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metal, high restraint, high heat input (see Incorrect welder technique, lack of crater   Incorrect filler metal, crack sensitive  parent metal, high restraint, high heat  Oxide films in or on parent metal, oxide  films in or on filler metal, oxygen in shield gas, poor gas shielding, inadequate  Poor gas c















                Causes  Chapter 2)  fill  input (see Chapter 2)  cathodic cleaning  mechanised set-up  Welder carelessness  parameters  Excessive grinding





                           Short longitudinal or star-shaped   Cracking in the HAZ or in  previously deposited weld metal  Oxide films trapped within the   Excessive oxide entrapment from   Accidental contact of the electrode  (TIG) or contact tip (MIG) Accidental arcing outside weld prep. Droplets of weld metal expelled









                Description  crack in finish crater  weld metal  weld pool turbulence  from weld pool











                Defect Name  Crater cracking  Liquation cracking  Oxide entrapment  Puckering  Tungsten or copper  inclusions  Stray arc strike  Spatter  Underflushing





           (cont.)


           Table 11.1  ISO 6520  Defect no.  104  100  303  3034  3041 (tungsten)  3042 (copper)  602  602  606
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