Low temperature polymer infiltration for rapid tooling

Common infiltration methods used in rapid tooling have certain limitations viz., cracks, distortion and shrinkage caused by high temperature infiltration. Poor surface quality is also a limitation of conventional infiltration techniques. The high temperatures involved in conventional infiltration techniques make the process more expensive, complex and difficult to control. To overcome these difficulties, as well as to generate tooling for a small batch production, a low temperature polymer infiltration method has been developed in conjunction with existing rapid tooling techniques. Based on the curing principles of polymer materials, several infiltration materials were selected and their mechanical and chemical characteristics were investigated. To determine the necessary amount of polymer materials and infiltration height in the sintered mold an infiltration model is derived and results compared with experimental data. Testing results have shown significant improvements in the thermal resistance and mechanical properties of the rapid tool as a result of the resin infiltration.