Different composite materials have been in used for many years in the automotive industry to create components that have unique characteristics, such as being strong and light. The trend in using composite materials is accelerating to meet lightweighting requirements to meet the next generation of fuel economy standards. An interesting lightweighting application combines the use of continuous fiber composite material with injection molding. The continuous fiber composite material forms a lightweight shell, while the necessary support structure can be created by overmolding it with a fiber-filled plastic. This so-called hybrid technique can create extremely lightweight strong parts that can be manufactured in large volumes. Autodesk® Simulation Moldflow® plastic injection molding simulation software can help with the design and engineering efforts for this process.
and Moldflow analysts
Mr. Nelson is an Autodesk software architect focusing on simulation of composite materials and structures. He has a master's degree in mechanical engineering from the University of Wyoming and a bachelors degree in mechanical engineering from North Dakota State University. Prior to joining Autodesk he served as the Chief Technology Officer at Firehole Composites.
This class reviews new functionality in Autodesk Simulation Moldflow Insight software and discusses recent and current research directions of Moldflow development. We cover the following capabilities: viscoelastic warp calculations, improved wall slip calculations, the influence of mold deflection, ejection force predictions, analysis of mold fatigue, flow imbalances (airflow), 3D compression molding, 3D conformal cooling, 3D hot runner elements, crystallization analysis, long fiber composites, and mesh preparation.
Autodesk® Simulation Moldflow® Insight is a powerful tool to simulate the different stages of the injection molding process. New capabilities of this tool include a transient mold thermal analysis. This type of simulation combines the mold filling and packing simulation with a heat transfer analysis, hence providing increased accuracy in the mold thermal solution. Attendees see the variables that influence the analysis results and improvements that can be done to the model to more closely correlate with the real life. For this purpose, simulation results are compared to experimental results over a design of experiments varying coolant temperature, injection rate, barrel temperature, and cooling time. The experimental results, obtained using an instrumented mold, include temperature and pressure data. Finally, the differences between the transient cooling analysis and the conventional cycle average solution are compared as well as their correlation to experimental results.
Injection-compression molding (ICM) is a process that results in reduction in molding pressure and the clamp force that is required to mold. Since the part experiences lower pressure gradient during molding, the residual stresses induced due to flow of material is reduced considerably. Due to this, and if everything else is kept constant, the final part warpage gets lowered significantly. This reduction in molded-in stresses also improves optical properties, which is important for applications requiring transparency. Also, ICM as a process is being used for molding of large parts, which otherwise require high tonnage presses to mold them. In this class, we investigate the influence of various parameters of the ICM process on final part warpage. The part considered here is a 2K molded part where the first shot can be molded using the conventional molding process. The second shot is injection-compression molded, keeping the first shot as a plastic insert.
Autodesk® Simulation Moldflow® Insight software offers the ability to predict the orientation of fibers in a molded part, and it has recently added a capability for predicting fiber length attrition. This information is useful for both short- and long-fiber molding compounds. But what lies behind these predictions? This class looks at the concepts behind the modeling of fiber orientation and fiber length. There are some equations, but the emphasis is on understanding the ideas behind each model. We start with the original fiber orientation model of Jeffery (from 1923!) and work up to the latest models for long-fiber molding compounds. We also look at the newest addition to this area—a model for process-induced changes in fiber length. The overall goal is to help attendees make smart choices about which orientation model to use and to understand how to choose the material parameters in each model.
This class reviews powerful analysis techniques that bring manufacturing knowledge together with detailed material modeling in order to perform comprehensive and accurate analysis of your parts, both as manufactured and in use. In addition, powerful optimization techniques allow the choice of the best gate location for your parts, and avoid over design of your parts, using a process of integrative optimization.
Microcellular Injection Molding (MuCell) is a mechanical foaming process used to improve the performance/weight characteristics of an injection-molded part. This class focuses on the Microcellular Injection Molding module for Autodesk® Simulation Moldflow® Insight. We explore how well the module correlates with real-world molded samples, determine the best approach for using the module for a brand new mold, and discuss any limitations to the module.