Metal Plasticity

Goal – Introduce a nonlinear metal plasticity material to the same large deflection model from the first workshop regarding the non-linear effects and compare/contrast results. Model Description 3D large deflection of spring plate –Spring plate –Ductile steel Loads and Boundary Conditions: –Fixed support –3 Mpa Pressure load at opposite end Metal plasticity – Goal and Desciption

Steps to Follow: Start an ANSYS Workbench session. Browse for and open “Spring_ws02A.wbdb” Workbench Projects file. – This project contains a Design Modeler (DM) geometry file “Spring_ws02A.agdb” and a Simulation (S) file “Spring_ws02A.dsdb”. Highlight the Model, Small Deflection-Linear Mat’l (Spring_ws02A.dsdb) file and open a Simulation Session. Metal Plasticity

Highlight the “Small Deflection- Linear Mat’l” Branch and duplicate this Branch with RMB=> Duplicate. Change the new branch name to “Large Deflection-Non Linear Mat’l” Add metal plasticity: – Highlight Geometry “Solid” branch – Activate Nonlinear Material Effects (YES) – Click on Structural Steel – Select Edit Structural Steel… Metal Plasticity – Non Linear Material

From the Engineering Data Tab – Select “Add/Remove Properties” From Add or Remove Properties Dialogue – Activate Bilinear Isotropic Hardening Plasticity – [OK] Metal Plasticity – Non Linear Material

Click on the ICON to the right of Bilinear Isotropic Hardening Define Yield Strength of 250Mpa and a Tangent Modulus of 10,000Mpa. Select “Close Curve” Metal Plasticity - Non Linear Material

In Details of “Analysis Settings” Branch and set up the following solution control specifications: Number of Steps* = 2 For Current Step = 1 – Auto Time Stepping = On Initial Substeps = 1 Minimum Substeps = 1 Maximum Substeps =1 – Weak Springs = Off – Large Deflection = On For Current Step = 2 – Auto Time Stepping = On Initial Substeps = 10 Minimum Substeps = 5 Maximum Substeps =100 – Weak Springs = Off – Large Deflection = On * Note: This will be run as a two step solution. Load step 1: zero pressure load. This null solution enables graphing force vs. deflection curve starting from zero. Load Step 2: Pressure = 3Mpa Metal Plasticity – Analysis Setting

Define “Pressure” over two load steps Metal Plasticity - Load

Highlight “Solution” Branch and insert the following additional items for post processing: – Equivalent Plastic Strain – Force Reaction Location Method = Boundary Condition Boundary Condition = Fixed Support Execute Solve Metal Plasticity – Solution Setup

This last solution run can take up to two minutes depending on machine. – Review the Solution Convergence History as before. – It now takes 45 iterations in nine substeps, including one bisection. Metal Plasticity - Solution

Review the displacement, stress and strain results and compare with the linear run. Note: Total Deformation is considerably large due to the onset of localized yielding near the support. Metal Plasticity - Solution

Plot Force vs Deformation: From Utility Menu, Insert “New Chart & Table” In the details of “Chart” insert 2 objects into Outline Selection: – Total Deformation – Force Reaction – Change X Axis to “Total Deformation (Max) – Define X and Y axis labels as “Deformation” and “Force” respectively – Output Quantites, Omit all but: Total Deformation (Max) Force Reaction (Total) Metal Plasticity - Force vs Deformation

Force vs Deformation (cont’d): Metal Plasticity - Force vs Deformation