An Example KDB File for AA6005 Al Alloy

Reference Folder: $Pandat_Installation_Folder\Pandat 2024 Examples\PanEvolution\AA6005_yield_strength\AA6xxx.kdb

This KDB file defines the kinetic parameters for the Mg5Si6 (b’) phase within the Al-Mg-Si alloys at the Al-rich side. The matrix phase is Fcc_A1-(Al) phase. This example AA6xxx.kdb can be used for most of the AA6xxx and AA3xx series of alloys. Again, some of the key kinetic parameters may need to be slightly revised according to the chemical compositions. Note that, the strengthening model is also included, which enables us to simulate the yield strength (σ) as well as its contributions (σi, σss, σp). Using the equation Eq. 10 in Precipitation Strengthening Model, the hardness can then be obtained as well. Table 7 in Section PanEvolution tables lists the strengthening model parameters defined in the precipitation database. These model parameters are adjustable and obtained via optimization to describe available experimental data.

<Alloy name="AA6xxx">

<MatrixPhase name="Fcc">

    <ParameterTable type="Strength" name="Parameters for Fcc">

      <Parameter type="Solution_Strengthening_Factor" name="Si"

value="66.3"

        description="solid solution strengthening scaling factor" />

      <Parameter type="Solution_Strengthening_Factor" name="Mg"

value="29"

        description="solid solution strengthening scaling factor" />

      <Parameter type="Solution_Strengthening_Factor" name="Cu"

value="46.4"

        description="solid solution strengthening scaling factor" />

      <Parameter type="Solution_Strengthening_Factor" name="Li"

value="20"

        description="solid solution strengthening scaling factor" />

      <Parameter type="Intrinsic_Strength" value="10" description=

        "intrinsic strength" />

      <Parameter type="Hardness_Factor" value="0.33" description=

        "intrinsic strength" />

      <Parameter type="Hardness_Constant" value="16" description=

        "intrinsic strength" />

    </ParameterTable >

    <ParameterTable type="kinetic" name="Parameters for (Al)">

      <Parameter type="Molar_Volume" value="1.0425E-5" description=

       "Molar Volume" />

    </ParameterTable >

  <PrecipitatePhase name="Mg5Si6" model="KWN" morphology="sphere"

    nucleation="Modified_Homo" growth="SFFK">

    <VariableTable name="Variables replacing built-in variables">

      <Parameter type="Nucleation_Barrier_Energy" value="7.475e-12/dgm(*)^2"

        description="Nucleation_Barrier_Energy" />

    </VariableTable >

    <ParameterTable type="kinetic" name="Parameters for kinetic model">

      <Parameter type="Molar_Volume" value="3.9e-5"

        description="Molar Volume" />

      <Parameter type="Interfacial_Energy" value="0.4"

        description="Interfacial Energy" />

      <Parameter type="Atomic_Spacing" value="4.05E-10"

        description="Atomic Spacing" />

     <Parameter type="Nucleation_Site_Parameter" value="0.3e-5"

        description="Nucleation Site Parameter" />

      <Parameter type="Steady_State_Nucleation_Rate" value="1"

        description="Indicate whether or not steady state nucleation rate" />

      <Parameter type="Driving_Force_Factor" value="1.0"

        description="Driving Force Factor" />

      <Parameter type="Kinetic_Parameter_Factor" value="3.0"

        description="a factor for kinetic parameter" />

      <Parameter type="Effective_Diffusivity_Factor" value="3"

        description="a factor for effective diffusivity" />        

    </ParameterTable >

    <ParameterTable type="strength" name="Parameters for

      strengthening models">

<Parameter type="Strength_Parameter" value="1.1e-5"

        description="th k_ppt in the equation" />

      <Parameter type="Shearing_Critical_Radius" value="5.0e-9"

        description="Critical size of shifting from shearing to looping" />

    </ParameterTable >

  </PrecipitatePhase >

</MatrixPhase >

</Alloy >