When using additive manufacturing (AM), several design considerations should be taken into account to optimise the technology’s potential. These considerations apply to a range of AM processes and can be both broad and specific to a particular AM process.
Key design considerations include:
Feature Size: It is critical to clearly define the limitations, including factors like feature size when designing lattice structures. The smallest feature size is closely tied to the specific AM method being employed.
Surface Quality: It is critical to clearly define the limitations, including factors like surface quality when designing lattice structures.
Support Structures: It is critical to clearly define the limitations, including the necessity for support structures when designing lattice structures. By tailoring lattice designs specifically for additive manufacturing, it becomes possible to minimise support structures.
Material Properties: A profound understanding of the material properties unique to LFAM is needed, including the behaviour of thermoplastic composites under varying printing conditions, such as temperature gradients and layer adhesion, which significantly impact the mechanical integrity and performance of the final product.
Complex Geometries: AM makes it possible to create complicated geometries and elaborate patterns that were previously impossible or prohibitive to manufacture using traditional manufacturing processes. AM enables the fabrication of parts with a complex shape as well as complex material distribution.
Multifunctional Components: AM allows for the integration of multifunctional components that traditional manufacturing methods cannot achieve.
Accuracy: Additive manufacturing introduces unique challenges such as accuracy.
Connectivity: Additive manufacturing introduces unique challenges such as connectivity.
AM Constraints: Designs should be optimised to maximise performance while considering AM constraints.
Minimum Feature Size: Structural design must account for factors such as minimum feature size.
Self-Supporting Characteristics: Structural design must account for self-supporting characteristics (avoiding critical overhangs).
Accessibility: Structural design must account for accessibility for removing unsolidified powder or resin.
Manufacturing Uncertainties: Geometric imperfections, material variations, and defects arising during the manufacturing process can result in significant deviations between the as-fabricated parts and their initial design models.
Build Orientation: Thorough build simulations should be conducted to identify the most effective orientation of components on the build platform. The orientation of the model during printing also requires careful consideration to optimise the print’s quality, strength, and the necessity for support structures.
Thermal Issues: For AM processes that use heat to fuse powder or feedstock, process consistency and part quality are strongly influenced by the temperature history inside the part during manufacture, especially for metal AM.
Scalability: The scalability of designs to large formats introduces issues related to structural stability, precision, and the mitigation of thermal distortion, requiring innovative computational models and simulation tools for accurate prediction and control.
Cost-effectiveness: Cost-effectiveness is a crucial consideration. AM can offer significant savings in terms of reduced material waste and simplified assembly, these benefits need to be weighed against the investment required for large- scale 3D printers and their operation.
Versatility: The versatility of AM, in terms of the range of employable materials, is another major consideration.
Reliability and Repeatability: The scalability, reliability, and repeatability of the process are essential considerations when evaluating LFAM’s viability. As the operation’s scale increases, it is imperative to ensure consistent quality control, process stability, and the ability to reliably reproduce results.
Furthermore, designers must have a thorough understanding of the defining characteristics of AM, as outlined by the commonly accepted ASTM and ISO standards, which describe AM as a method of producing 3D objects through the layer-by-layer addition of materials, with the production process being based on a digital model that is sliced into layers. A number of critical factors influence the design process such as design complexity, material considerations and technology limitations.
If you have a specific project in mind or indeed you simply wish to explore the potential of additive manufacturing within your organisation please feel free to contact us.