# Category: Theory

### Best Material Model for Nylon (PA66)

Nylon is a commonly used in industrial applications. This article examines which material model is most accurate for Nylon PA66.

### WLF or Arrhenius – Which is Better?

This article shows that the WLF equation is always the same or better than the Arrhenius model.

### Flow Cessation is Important for Viscoplasticity

This article shows how to fix 2 common problems with viscoplastic material models: E-modulus and large-strain stress.

### Basic FEA Theory – Part 5 – Solve For Displacements

Last article is in my series on basic FEA theory. In this article I put everything together to solve for the displacements.

### Basic FEA Theory – Part 3 – Strain Calculation

The article shows how to calculate the strain components from the nodal displacements in a linear finite element calculation.

### Basic FEA Theory – Part 1 – Principle of Virtual Work

Derivation of the equation of virtual work in discretized form. The presented results are the foundation to the Finite Element method.

### Full Finite Element Solver in 200 Lines of Python

Tutorial on how to write a full FE solver in 200 lines of Python code. This is part 2 in our series. The focus is on using an external file.

### Full Finite Element Solver in 100 Lines of Python

Tutorial on how to write a full FE solver in 100 lines of Python. This is part one of this tutorial series.