MOLDS FOR COMPOSITES: Hybrid Technology Development to Directly Print Thermoset Molds for Composites.

The manufacturing of composite parts and assemblies requires various kinds of tools, which determine the accuracy, performance, and cost of the end component. Additive manufacturing (AM), also known as 3D printing technology, has a direct impact on the manufacturing the of composite structures by offering rapid production of molds. 3D printing of molds, jigs and fixtures for composites manufacturing increases flexibility and design opportunities and reduces costs and lead time. Large-format AM systems, that can create an object larger than 1 m3, are the only systems that are suitable for rapid production of molds. Most of these systems are based on single-screw thermoplastic pellet extruders. Massivit 3D has developed a unique technology called Cast-In-Motion (CIM) and a designated system, the Massivit 10000, for direct digital printing of tools and molds, made of a proprietary epoxy-based, Thermoset casting material, CIM 500. The technology consists of printing a double-wall shell made of a proprietary UVcured Water Breakable (WB) material, Dimengel 50, followed by casting a calculated amount of CIM 500. The WB printing process and the thermoset-casting processes operate intermittently to create a near net shape, thermoset mold encapsulated by the WB shell. After the encapsulated mold is cured to optimize its mechanical properties at elevated temperatures, it is immersed in a water bath which causes the shell to crumble away and can be post finished to obtain the desired surface finish and geometry for the mold. The system can also be used for the printing of geometric cores and soluble mandrels for the composites industry by utilizing the printing of the WB and other various acrylic base UV cured materials without the conjunction of the CIM 500. This paper presents the advancements in CIM technology with its proprietary materials to enable direct manufacturing of complex finished molds. It also presents various applications from the design phase through printing to post finishing that meet customers' requirements. [ABSTRACT FROM AUTHOR]