Metal Plasticity

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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 plateSpring plateDuctile steel

Loads and Boundary Conditions:Fixed support3 Mpa Pressure load at opposite end Metal plasticity Goal and Desciption

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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 Matl (Spring_ws02A.dsdb) file and open a Simulation Session.

Metal Plasticity

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Highlight the Small Deflection- Linear Matl Branch and duplicate this Branch with RMB=> Duplicate.

Change the new branch name to Large Deflection-Non Linear Matl

Add metal plasticity:

Highlight Geometry Solid branchActivate Nonlinear Material Effects (YES)Click on Structural SteelSelect Edit Structural SteelMetal Plasticity Non Linear Material

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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

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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

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In Details of Analysis Settings Branch and set up the following solution control specifications:

Number of Steps* = 2For Current Step = 1Auto Time Stepping = OnInitial Substeps = 1Minimum Substeps = 1Maximum Substeps =1Weak Springs = OffLarge Deflection = OnFor Current Step = 2Auto Time Stepping = OnInitial Substeps = 10Minimum Substeps = 5Maximum Substeps =100Weak Springs = OffLarge 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 = 3MpaMetal Plasticity Analysis Setting

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Define Pressure over two load steps

Metal Plasticity - Load

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Highlight Solution Branch and insert the following additional items for post processing:

Equivalent Plastic StrainForce ReactionLocation Method = Boundary ConditionBoundary Condition = Fixed Support

Execute Solve

Metal Plasticity Solution Setup

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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

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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

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Plot Force vs Deformation:

From Utility Menu, Insert New Chart & Table

In the details of Chart insert 2 objects into Outline Selection:

Total DeformationForce 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

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Force vs Deformation (contd): Metal Plasticity - Force vs Deformation

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