FEA Software

To analyze fatigue life, the stresses and/or strains must be calculated.  Finite element analysis (FEA) is indispensable nowadays.  The following are the most popular FEA software packages.  Fatigue+ and SFAT can directly import stress/strain/temperature results generated by ANSYS through .rst files.  Stress/strain/temperature history files generated by other FEA packages can also be imported and processed through text files.


ANSYS, Inc. is an American Computer-aided engineering software developer headquartered south of Pittsburgh in Cecil Township, Pennsylvania, United States. ANSYS publishes engineering analysis software across a range of disciplines including finite element analysis, structural analysis, computational fluid dynamics, explicit and implicit methods, and heat transfer.

The company was founded in 1970. by John A. Swanson as Swanson Analysis Systems, Inc (SASI). Its primary purpose was to develop and market finite element analysis software for structural physics that could simulate static (stationary), dynamic (moving) and thermal (heat transfer) problems. SASI developed its business in parallel with the growth in computer technology and engineering needs. The company grew by 10 percent to 20 percent each year, and in 1994 it was sold to TA Associates. The new owners took SASI’s leading software, called ANSYS, as their flagship product and designated ANSYS, Inc. as the new company name.

Fatigue+ and SFAT fatigue life analysis software use .rst interface to read stresses, strains and temperatures from ANSYS result file.


Abaqus FEA (formerly ABAQUS) is a software suite for finite element analysis and computer-aided engineering, originally released in 1978. The name and logo of this software are based on the abacus calculation tool. The Abaqus product suite consists of five core software products:

  1. Abaqus/CAE, or “Complete Abaqus Environment” (a backronym with an obvious root in Computer-Aided Engineering). It is a software application used for both the modeling and analysis of mechanical components and assemblies (pre-processing) and visualizing the finite element analysis result. A subset of Abaqus/CAE including only the post-processing module can be launched independently in the Abaqus/Viewer product.
  2. Abaqus/Standard, a general-purpose Finite-Element analyzer that employs implicit integration scheme (traditional).
  3. Abaqus/Explicit, a special-purpose Finite-Element analyzer that employs explicit integration scheme to solve highly nonlinear systems with many complex contacts under transient loads.
  4. Abaqus/CFD, a Computational Fluid Dynamics software application which provides advanced computational fluid dynamics capabilities with extensive support for preprocessing and postprocessing provided in Abaqus/CAE.
  5. Abaqus/Electromagnetic, a Computational electromagnetics software application which solves advanced computational electromagnetic problems.

The Abaqus products use the open-source scripting language Python for scripting and customization. Abaqus/CAE uses the fox-toolkit for GUI development.

Abaqus is used in the automotive, aerospace, and industrial products industries. The product is popular with academic and research institutions due to the wide material modeling capability, and the program’s ability to be customized. Abaqus also provides a good collection of multiphysics capabilities, such as coupled acoustic-structural, piezoelectric, and structural-pore capabilities, making it attractive for production-level simulations where multiple fields need to be coupled.

Abaqus was initially designed to address non-linear physical behavior; as a result, the package has an extensive range of material models such as elastomeric (rubberlike) material capabilities.


NASTRAN is a finite element analysis (FEA) program that was originally developed for NASA in the late 1960s by Stephen Burns of the University of Rochester under United States government funding for the aerospace industry. The MacNeal-Schwendler Corporation (MSC) was one of the principal and original developers of the publicly available NASTRAN code.  NASTRAN source code is integrated in a number of different software packages, which are distributed by a range of companies.

NASTRAN is written primarily in FORTRAN and contains over one million lines of code. NASTRAN is compatible with a large variety of computers and operating systems ranging from small workstations to the largest supercomputers.

NASTRAN was designed from the beginning to consist of several modules. A module is a collection of FORTRAN subroutines designed to perform a specific task—processing model geometry, assembling matrices, applying constraints, solving matrix problems, calculating output quantities, conversing with the database, printing the solution, and so on. The modules are controlled by an internal language called the Direct Matrix Abstraction Program (DMAP).

Each type of analysis available is called a solution sequence.

Some of the most common solution sequence codes are:

  • 101 – Linear Static
  • 103 – Modal
  • 105 – Buckling
  • 106 – Non-Linear Static
  • 107 – Direct Complex Eigenvalue
  • 108 – Direct Frequency Response
  • 109 – Direct Transient Response
  • 110 – Modal Complex Eigenvalue
  • 111 – Modal Frequency Response
  • 112 – Modal Transient Response
  • 129 – Nonlinear Transient
  • 144 – Static Aeroelastic Analysis
  • 145 – Flutter / Aeroservoelastic analysis
  • 146 – Dynamic Aeroelastic Analysis
  • 153 – Non-Linear static coupled with heat transfer
  • 159 – Nonlinear Transient coupled with Heat transfer
  • 187 – Dynamic Design Analysis Method
  • 200 – Design Optimization and Sensitivity analysis
  • 400 – Non-Linear Static and Dynamic (implicit) (MSC.NASTRAN native, supersedes 106, 129, 153 and 159 – part of MSC.NASTRAN)
  • 600 – Non-Linear Static and Dynamic (implicit) (front end to MSC.Marc – part of MSC.NASTRAN)
  • 601 – Implicit Non-Linear (ADINA for NX Nastran)
  • 700 – Explicit Non-Linear (LS Dyna plus MSC.Dytran – part of MSC.NASTRAN)
  • 701 – Explicit Non-Linear (ADINA for NX Nastran)

MSC Nastran

MSC Nastran is the original commercial Nastran product started by Dr. Richard MacNeal in 1963. MSC Nastran is commonly utilized for performing structural analysis. Although utilized in every industry, it maintains a strong following in aerospace and automotive industries for performing computational stress and strain analysis of component and system level models of structures. Since 1963, MSC Nastran has continued to evolve and extend capabilities to dynamics, rotordynamics, nonlinear, thermal, high impact, NVH, fluid structural interactive and fatigue analysis. Today it couples with MSC Marc and LS-Dyna to provide highly nonlinear coupled analysis solutions.


Built from the same base code as the original NASTRAN software created by NASA that includes the original NASTRAN architecture and DMAP language, NASTRAN-xMG provides unlimited problem size, high-speed solver technology, and substructuring analysis options. The principal founder of the company is Dr. Richard H. MacNeal.

NEi Nastran

NEi Nastran is a general purpose finite element analysis solver used to analyze linear and nonlinear stress, dynamics, and heat transfer characteristics of structures and mechanical components. It is available on a variety of platforms including 32/64-bit Windows and Linux. This software was acquired by Autodesk in May 2014.

NX Nastran

NX Nastran resulted from an FTC action against MSC Corporation for alleged antitrust activity. The antitrust settlement allowed the 2003 purchase of a royalty-free, perpetual license for the MSC.Nastran 2001 source code by UGS. UGS was previously the Unigraphics division of EDS. Nastran’s CAE capabilities were added to NX Unigraphics’ CAD and other components to form the EDS/UGS PLM Solutions product life-cycle management suite. This product line was acquired by SIEMENS in 2007 and became SIEMENS PLM Software.

The purchase included a perpetual, worldwide, free of royalties, nonexclusive license of the software program MSC.Nastran v2001, other assets related to the software, and all copyright and trademark rights acquired as a result of MSC’s acquisitions of Universal Analytics Inc. and Computerized Structural Analysis & Research Corp. in 1999.

NX Nastran is now part of Siemens PLM Software’s Simcenter 3D product portfolio.

OCF Nastran

Both source and binary copies of Nastran are available from the Open Channel Foundation for an annual license fee. This was part of the NASA COSMIC Collection distribution from the National Technology Transfer Center.


The success of NASTRAN led to development of many other finite element software. One such software is ASTROS that extended NASTRAN type capability to include structural optimization. Currently ASTROS is maintained by Zona Technology, Inc