Common infiltration methods used in rapid tooling have certain limitations viz., cracks, distortion and shrinkage caused by the high temperature of processing. Poor surface quality also is a limitation of most infiltration techniques. In addition, the high temperatures involved in conventional infiltration techniques make the process more costly, complex and difficult to control. To overcome the above mentioned difficulties a low temperature polymer infiltration method is studied and used in a rapid tooling technique, Rapid Pattern Based Powder Sintering (RPBPS). Based on the curing principles of polymer materials, several potential infiltration materials were selected. Using various infiltration methods and materials a series of testing samples were made and their mechanical properties were tested. In order to calculate the necessary amount of polymer materials and the height of infiltration into the sintered mold/part an infiltration model is also proposed and the results are compared with experimental data. The low temperature infiltration resulted in a 39.8% increase in the bending strength of the sintered and infiltrated part as compared to the sintered-only part. The low temperature infiltration helped to control the shrinkage during infiltration to less than 0.5% and also eliminate distortion of the final product.
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