Impact — The Complete Guide: Free Explicit Finite Elements for Crash and Impact

Impact is open-source finite element software for explicit dynamic analysis. This approach suits events lasting milliseconds — impact, crash or sheet forming — where an implicit solver struggles to converge because of contact, large deformation and rapid change.

Impact FEM

Impact FEM Project

An explicit dynamic finite-element solver for impact and crash problems.

Get it from the vendor

What you get

Explicit solver — marches in small time steps without solving a large system of equations at every step.
Drop tests — what happens to a part or an enclosure dropped onto a surface.
Crash and forming — large deformation and contact between bodies.
Pre- and post-processor — a simple tool to prepare the model and display results.
Java — runs on Windows, Linux and macOS with a Java runtime.

What to know

Impact is a small project, and its documentation and community are limited compared with large solvers. It suits learning the principles of explicit analysis and simple models. For industrial work with advanced material models, failure and an active community — OpenRadioss.

Related tools

For industrial-grade explicit analysis — OpenRadioss. For implicit static and dynamic analysis with an interface — PrePoMax with CalculiX. To view results — ParaView.