Changing the Design Process
Additive manufacturing has not only changed the way things are being built, but how they are designed. SIMULIA CTO Bruce Engelmann believes that additive techniques have the potential to revolutionize the manufacturing industry, such as Henry Ford did with the automotive industry back in the early 1900s. â€œBefore Henry Ford the only cars on the road were built in custom shopsâ€ says Bruce. â€œFord re-imagined how cars could be built on assembly lines.â€
With additive techniques, it is now commonplace for designers and engineers to manufacture prototypes in-house. The way prototypes are manufactured differs from prototypes of the past. For example, with traditional fabrication techniques such as CNC or casting, only the exterior surface is considered in the design cycle.
Light-weighting of structures has been extremely important for years in aerospace and automotive industries. Light-weighting can be achieved through topology optimization, which creates organic structures tailored to specified in-service loads. â€œIn addition to capturing the physics of material behaviors, we’re giving designers the freedom to lightweight their designs without compromising performance,â€ says Bruce Engelmann. For more information about how topology optimization can be used for additive manufacturing, check out, â€œTopology Optimization for Additive Manufacturing Applicationsâ€, by Sakya Tripathy.
Much like with traditional techniques, build parameters during the additive process must be considered before manufacturing. Because AM is a layer-by-layer manufacturing process, there must be sufficient support beneath the layers to ensure that the material stays in place. If a layer is not properly supported, this is known as an overhang region. The common practice is to add support structures during the printing process and remove them during post processing. The removal of support structures can be difficult, time consuming and a waste of resources. In order to minimize the dependence of support structures, the build orientation is defined and overhang regions can be identified. In Figure 1, the overhang region is highlighted in red.
The designer can then decide if they want to change the design or add support structures. â€œWith optimization, you may be able to eliminate constraints, such as support structures, entirely.â€ Says Bruce Engelmann.
Support structures are one of many parameters that are considered when using additive manufacturing. Other parameters, such as tool path parameters, scan strategies and build environment conditions can also be included in the design cycle. Using the custom build parameters, designers and engineers are able to predict part distortions and residual stresses before leaving the design environment.
Once a design has been chosen, it can be structurally validated by simulating in-service loads. â€œAnd what better way to virtually test for fracture, failure and durability performance than using the non-linear simulation technologies of Abaqus,â€ says Bruce Engelmann.
â€œThe best part is that we are providing companies the ability to truly go end-to-end, from engineering the material, designing the parts, simulating the process and predicting part life, all within our 3DEXPERIENCE platform.â€
By Andrew Wysocki, Technical Specialist with the SIMULIA Innovation Lab