Solidification
Analysis
The solidification phenomena of metal can be
characterized as a phase change phenomena generated by a temperature
change. For the solidification of aluminum alloy, iron alloy, magnesium
alloy, which are usually used in Die Cast parts, latent heat is discharged
at a certain temperature area, based upon the growth of the dendrite. It is
extremely difficult to consider the micro-phenomena when performing a solidification analysis.
In this product we considered both aspects of the solid phase boundary
and the liquid phase boundary and handle the subject as a 3 area matter.
Namely, we perform a solidification analysis by averaging and expressing the effects of
the dendrite growth as change
rates of a solid phase. We have adopted the Enthalpy to handle the phase change phenomenon.
Enthalpy looks at the phase change phenomenon as heat capacity
and it is able to handle in unity the Enthalpy as a parameter in terms of
the analysis system.
SOLIDIFICATION SIMULATION APPLICATION EXAMPLE
After applying the solidification simulation program to the actual
Die Cast part, estimations on the locations of casting defects that may occur
during solidification are indicated below in Figure 1. Analysis of the cellular phone part is the same as in the fluid flow simulation application example, and is
also produced by aluminum Die Cast. Divided 547 ways in the X direction,
251 ways in the Y direction, 78 ways in the Z direction with one edge of 0.255mm.
All together it made a 10,709,166 element mesh. It
required about 2 minutes to divide on a pre-processor. Indicated below is the hardware environment used in the analysis.
SOLIDIFICATION ANALYSIS
Hardware: COMPAQ DS20E（MPU:667MHz RAM:4GB ） A solidification analysis
was conducted concerning the above mentioned analysis
terms. The material properties used in the solidification analysis are indicated
in
Table 1, and the required time and memory used for the analysis are indicated
in Table２.
Table 1 Material Property
|
|
Density |
Thermal Conductivity |
Specific Heat |
Initial Temp. |
|
Metal Mold(SDK61) |
7.8 g/cm3 |
0.102
cal/cm・s・C |
0.100
cal/g・C |
200 deg. C |
|
Casting Product(ADC12) |
2.8 g/cm3 |
0.230
cal/cm・s・C |
0.240
cal/g・C |
680 deg. C |
Table 2 Analysis Time
and Memory Usage
|
|
Analysis Time |
Memory Used |
|
Solidification Analysis |
2.7hrs. |
228 MB |
Figure 1 Results of Solidification Analysis
