UMAT is the most popular subroutine code in Abaqus. This code is developed to define new material behaviour for modelling. However, many students incorrectly consider this code for parametric definitions. The following information presents some alternative explanations on UMAT.
Abaqus UMAT calculations are divided into calculating Stress and calculating Tangent Moduli. There are several functions and variables in Abaqus UMAT which helps you to:
- Implement the general constitutive equation.
- Define any constitutive model of arbitrary complexity.
- Use user-defined material models with any ABAQUS structural element type.
- Apply multiple user materials in a single UMAT routine and can be used together.
Here you can download a PDF file to understand how to use Abaqus UMAT code. This file is provided by Saeid Poorasadion from Sharif university of technology.