A new rapid tooling technique and its special binder study

摘要

A new rapid tooling technique named Rapid Pattern Based Powder Sintering (RPBPS) has been developed. It comprises the steps of first building a pattern made of polymer materials using a rapid prototyping machine based on a 3-D CAD model. Thepattern is positioned on a substrate in a box or frame, then a mixture of metal (ceramic or polymer) powder and binder is cast around the pattern. Next, there is a step of removing the pattern and separating the substrate to obtain a green compact thathas the desired cavity. Then the green compact will be sintered and/or infiltrated to form a tool or part. The new technique has the advantages of using a variety of materials, rapidity, making complex geometry parts and low cost, compared with severalexisting rapid tooling techniques. Many key technical problems in RPBPS are related to the binder. In order to select a suitable binder, the heat deformation resistance and heat stabilization of some polymer materials are discussed in depth.