Micro Shrinkage

Micro shrinkage is a form of filamentary shrinkage in which the cavities are very small, but large in number and can be distributed over a significant area of the casting. Some of the criteria functions used to predict casting soundness. The criterion functions such as SUT, Niyama, LCC, and KCL can be used to predict micro porosity formation during solidification. Porosity criteria have been used in the computer simulation of solidification in casting to evaluate macro and micro porosity in short and long freezing range alloys. SUTCAST software is capable to show those functions.

SUT   Niyama

[SUT]                                                                                     [Niyama]

[SUT]: Computational cells containing a solid fraction exceeding the Critical solid fraction can have Micro porosity. The rate and value between solid fraction and critical solid fraction can predict the amount of shrinkage in that cell during that time step.SUT criterion highly recommended for anticipating micro shrinkage in cast iron parts

[Niyama] criterion is capable of predicting the probability of leakage due to interconnected macro or micro-shrinkage porosity. This model is able to predict not only the gross type of shrinkage but also finer ones like center line shrinkages

[KCL and LCC] criterion functions are used to predict the porosity formation of aluminum alloys. For the long freezing range aluminum alloys, LCC criterion shows the better result, SUTCAST possesses this value which makes the software more flexible for users.

The location and distribution of microporosities are well predicted using SUTCAST sophisticated models.

 

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