The final linear dimension of the casting depends on the cumulative effects of the linear expansions or contractions in each step of the investment casting process. In most cases, the mold geometry or cores restrict the shrinkage of the pattern or the cast part, and the final casting dimensions may be affected by time-dependent processes such as viscoelastic deformation of the wax, and viscoplastic creep and plastic deformations of the shell and alloy. The complexity of shape and the close dimensional tolerances required in the final casting make it difficult to determine tooling dimensions for the investment casting process. Thus, the pattern die is often reworked several times to produce castings whose dimensions are within acceptable tolerances.

The program will determine which properties of the wax, shell and alloy contribute to the dimensional changes, identify and quantify the tests needed to obtain these properties and then develop a computer model to incorporate these results and predict final tooling dimensions needed to produce a dimensionally acceptable metal casting.