> Simulation > Material Properties > Material Models > Linear Elastic Isotropic Model
What's New
User Interface
SolidWorks Fundamentals
Moving from 2D to 3D
Design Checker
Design Studies in SolidWorks
Detailing and Drawings
Mold Design
Motion Studies
Parts and Features
PhotoView 360
Sheet Metal
Welcome to SolidWorks Simulation Online Help
Access to Help
Legal Notices
Analysis Background
Simulation Fundamentals
Simulation Interface
Simulation Studies
Composite Shells
Loads and Restraints
Material Properties
Assigning Materials
Applying a Material
Removing a Material
Creating a Custom Material
Creating a Material Library
Managing Favorite Materials
Using Drag and Drop to Define Materials
Material Properties Used in SolidWorks Simulation
Isotropic and Orthotropic Materials
Temperature - Dependent Material Properties
Defining Stress-Strain Curves
Material Dialog Box
Material Models
Material Models
Plasticity Drucker - Prager Model
Plasticity Tresca Model
Plasticity von Mises Model
Viscoelastic Model
Linear Elastic Orthotropic Model
Linear Elastic Isotropic Model
Hyperelastic Ogden Model
Hyperelastic Mooney - Rivlin Model
Nitinol Material Model
Nonlinear Elastic Model
Creep Models
Comparison of Tresca and von Mises Criteria for Plasticity
Generalized Maxwell Model
Hyperelastic Blatz - Ko Model
Design Studies
Analysis Library
Viewing Results
Study Reports
Checking Stress Results
Simulation Options
Sustainability Products
SolidWorks Utilities
Workgroup PDM
Hide Table of Contents Show Table of Contents

Linear Elastic Isotropic Model

A material is said to be isotropic if its properties do not vary with direction. Isotropic materials therefore have identical elastic modulus, Poisson's ratio, coefficient of thermal expansion, thermal conductivity, etc. in all directions. The term isothermal is some times used to denote materials with no preferred directions for coefficients of thermal expansion.

In order to define the isotropic elastic properties, you must define the elastic modulus Ex .  The program assumes a value of 0.0 for Poisson's ratio nxy,if  no specific value is specified.  A common value for the Poisson's ratio is 0.3. The shear modulus Gxy. is calculated internally by the program even if it is explicitly specified.

The stiffness matrix for an isotropic material contains only two independent coefficients. The following sections describe the isotropic stress-strain relations in two- and three-dimensions including the effect of thermal strains.

Isotropic Stress-Strain Relations

The most general form of the isotropic stress-strain relations including thermal effects is shown below:

Assumptions of Linear Elastic Material Models

Linear elastic material models make the following assumptions:

  • Linearity Assumption. The induced response is directly proportional to the applied loads. For example, if you double the magnitude of loads, the model's response (displacements, strains, and stresses) will double. You can make the linearity assumption if the following conditions are satisfied:

  • The highest stress is in the linear range of the stress-strain curve characterized by a straight line starting from the origin. As the stress increases, materials demonstrate nonlinear behavior above a certain stress level. This assumption asserts that the stress should be below this level. Some materials, like rubber, demonstrate a nonlinear stress-strain relationship even for low stresses.

  • The maximum displacement is considerably smaller than the characteristic dimension of the model. For example, the maximum displacement of a plate must be considerably smaller than its thickness and the maximum displacement of a beam must be considerably smaller than the smallest dimension of its cross-section.

  • Elasticity Assumption. The loads do not cause any permanent deformation. In other words, the model is assumed to be perfectly elastic. A perfectly elastic model returns to its original shape when the loads are removed.

Isotropic vs. orthotropic materials


MySolidWorks Search

Provide feedback on this topic

SOLIDWORKS welcomes your feedback concerning the presentation, accuracy, and thoroughness of the documentation. Use the form below to send your comments and suggestions about this topic directly to our documentation team. The documentation team cannot answer technical support questions. Click here for information about technical support.

* Required

Subject:   Feedback on Help Topics
Page:   Linear Elastic Isotropic Model

We have detected you are using a browser version older than Internet Explorer 7. For optimized display, we suggest upgrading your browser to Internet Explorer 7 or newer.

 Never show this message again

Web Help Content Version: SOLIDWORKS 2010 SP05

The search functionality within the web help is in a beta test phase and you may experience periodic delays or interruptions in its performance. These are the normal and ordinary features of a beta test and shall not under any circumstances give rise to any liability on the part of Dassault Systèmes SolidWorks Corporation or its licensors. The topics within the Web-based help are not beta topics; they document SOLIDWORKS 2010 SP05.

To disable Web help from within SOLIDWORKS and use local help instead, click Help > Use SOLIDWORKS Web Help.

To report problems encountered with the Web help interface and search, contact your local support representative. To provide feedback on individual help topics, use the “Feedback on this topic” link on the individual topic page.