Influence of defects on strength of industrial aluminum alloy Al–Si 319

The effect of cooling rate, chemical composition, and type of heat treatment and microstructural architecture of cast Al–Si 319 industrial alloy has been quantified using the cumulative Weibull distribution. This allows a particular figure to quantify the spread of the data with the Weibull modulus. Modulus was found to vary from 12.47 to 68.64, and characteristic life was found to vary from 201.48 to 347.89 MPa depending on processing conditions of the material. Fractographic examination of the castings showed tangled networks of oxide films, which are actually cracks in the casting. Oxide films are normally observed in the fracture surfaces of the specimens. The mechanical properties depend primarily on defects of the population instead of other factors.