Finite element analysis (FEA) is a computer-based method of analyzing and simulating the behavior of components under a variety of conditions, including force, temperature, vibration, and motion. FEA calculates displacements, strains, and stresses under internal and external loads. These predictions confirm if a design is suitable or if modifications are required to prevent failure.
This tutorial comes courtesy of Stratasys.
Step 1: Overview
FEA results are presented as on-screen, digital models with color mapping for a visual depiction of the effects of applied conditions (Figure 1). These models may also show the resulting change to a component’s geometry as it deforms under the applied load.
To bring FEA results into the real word, PolyJetTM 3D Printers create physical models that retain the FEA color mapping (Figure 2). Rather than interpreting results from a computer screen, designers and engineers can visualize the analysis with models that are hand-held. The results can be printed in an “as-designed” or “load-deformed” state (Figure 3).
Common applications for 3D printed FEA results include:Design verification Failure analysis Material selection Design review meetings Marketing presentations
Finite element analysis yields better component performance. When coupled with PolyJet, design and material options become clearer, leading to better products.
Step 2: Perform FEA Calculation
Using available FEA software, import a CAD model, assign a material, define conditions, and specify fixed positions. Run the analysis (Figure 4).
Step 3: Create VRML Files
NOTE: The following procedures are for SolidWorks software. However, the process will be similar for other FEA software programs. Please consult the appropriate user manuals for specific commands.
With the FEA results plot displayed, create the VRML for the first color range depicted in the color map. Do this by first selecting Plot Tools > Iso Clipping. Confirm that the Reverse clipping direction icon is not selected for Iso 1. Also confirm that the Iso 2 box is not selected. Move the scroll bar for the Iso 1 value so that it includes all of the desired first-color results. With inactive, the display shows only the results above the selected value (Figure 5).
Click the green checkmark to confirm the selection. Save the Iso clipping file as a VRML by selecting Plot Tools > Save As and then select the VRML file from the Save as type dropdown menu. This creates the first shell for 3D printing.
Repeat the above steps for subsequent shell color ranges by using both Iso 1 and Iso 2 to create a value range (Figure 6).
For example, to create the second shell, use the Iso 2 scroll bar to set the lower limit. Leaving Iso 1 at its previous value, click the Reverse clipping direction icon so that only lower values are displayed. To create the third shell, toggle both Iso 1 and Iso 2 Reverse clipping direction icons and adjust the displayed value for Iso 1.
After creating VRML les for all regions of the model, the VRML le creation procedure is complete.
Step 4: Create STL Files
Open Materialize MagicsTM or any other STL manipulation program. Import all Iso clipping files (VRMLs) created in section 1.2. Select File > Import Part, select all files and then click Open. When prompted, select OK (Figure 7).
After importing into Magics, there will be empty files that need to be unloaded. Click to view each file to see if it contains any elements of the model. Select all files with no content and then click Unload Parts. When prompted with the option to save each file, select No to All. Now check the box for all of the files that remain to select them. Next, save the files as STLs using File > Save Part(s) As and select the STL format. Create STL file procedure complete.
Step 5: Print FEA Model
Open Objet StudioTM and import all of the STL files saved in section 1.3. Using the Insert Part function, select all of the STL files and check the Assembly box. Then click Insert (Figure 8).
Assign the desired material and color to each shell. Select a shell and then assign the color by selecting it from the material drop down menu (Figure 9).
Repeat as needed. Complete the file preparation process using the standard PolyJet workflow. Initiate PolyJet print job. Print FEA model procedure complete (Figure 10).