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wiki/concepts/Abaqus Hyperelastic and Viscoelastic Materials.md

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+---
+type: concept
+title: "Abaqus Hyperelastic and Viscoelastic Materials"
+complexity: advanced
+domain: computational-mechanics
+created: 2026-06-01
+updated: 2026-06-01
+address: c-000095
+aliases:
+  - Abaqus hyperelasticity
+  - Abaqus viscoelasticity
+  - Abaqus elastomer materials
+  - Abaqus Mullins effect
+tags:
+  - concept
+  - finite-element-method
+  - abaqus
+  - hyperelasticity
+  - viscoelasticity
+  - materials
+status: current
+related:
+  - "[[Abaqus-Analysis-User-s-Guide-Volume-III|Abaqus Analysis User's Guide Volume III]]"
+  - "[[Abaqus Elastic Material Models]]"
+  - "[[Hybrid Incompressible Elements]]"
+  - "[[Nonlinear Finite Element Analysis]]"
+  - "[[Abaqus Thermal Expansion and Damping Materials]]"
+sources:
+  - "[[Abaqus-Analysis-User-s-Guide-Volume-III|Abaqus Analysis User's Guide Volume III]]"
+---
+
+# Abaqus Hyperelastic and Viscoelastic Materials
+
+## Definition
+
+Abaqus hyperelastic and viscoelastic material models describe large-strain recoverable response and time- or frequency-dependent response, especially for rubberlike materials and elastomeric foams.
+
+## How It Works
+
+Hyperelastic models use strain energy potentials to describe finite-strain elastic response. The source lists rubberlike isotropic hyperelasticity, elastomeric foams, and anisotropic hyperelastic behavior. Rubberlike materials are often nearly incompressible, so Abaqus/Standard commonly requires hybrid continuum elements for highly confined nearly incompressible cases, while Abaqus/Explicit requires explicit compressibility because it cannot enforce exact incompressibility at each material point.
+
+The guide also covers stress softening and dissipation in elastomers. Mullins-effect modeling reduces stiffness after prior loading; elastomeric foam energy dissipation and permanent set models capture hysteretic or residual effects.
+
+Viscoelastic behavior appears in time-domain and frequency-domain forms. Time-domain models use relaxation behavior, while frequency-domain models describe storage and loss response. Nonlinear viscoelastic capabilities include hysteresis in elastomers and the parallel rheological framework.
+
+## Why It Matters
+
+Elastomer and foam models are strongly tied to nonlinear geometry, incompressibility, test-data calibration, and dissipation. A stable element and procedure choice is part of the material model, not a separate afterthought.
+
+## Connections
+
+- [[Hybrid Incompressible Elements]] are often required for nearly incompressible hyperelastic solids in Abaqus/Standard.
+- [[Nonlinear Finite Element Analysis]] supplies the finite-strain and contact-capable solution setting these models usually need.
+- [[Abaqus Thermal Expansion and Damping Materials]] connects thermal expansion and damping behavior that may be combined with elastomer models.
+
+## Sources
+
+- [[Abaqus-Analysis-User-s-Guide-Volume-III|Abaqus Analysis User's Guide Volume III]]
+