--- type: concept title: "Abaqus Nonlinear Solution Control" complexity: advanced domain: computational-mechanics created: 2026-05-29 updated: 2026-05-29 address: c-000081 aliases: - Abaqus convergence controls - Abaqus nonlinear controls - Abaqus Newton iteration controls tags: - concept - finite-element-method - abaqus - nonlinear-analysis - convergence status: current related: - "[[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]]" - "[[Nonlinear Finite Element Analysis]]" - "[[Static Equilibrium Equation Solvers]]" - "[[Direct Time Integration Methods]]" - "[[Abaqus Analysis Procedures]]" sources: - "[[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]]" --- # Abaqus Nonlinear Solution Control ## Definition Abaqus nonlinear solution control is the set of increment, iteration, convergence, stabilization, and time-integration accuracy settings used by Abaqus/Standard to solve nonlinear analyses. ## How It Works In nonlinear Abaqus/Standard procedures, a step is broken into increments. At the end of each increment Abaqus attempts to find an equilibrium configuration. Each iteration computes a correction using a tangent stiffness, updates the configuration, computes internal forces, and compares residuals and corrections against convergence criteria. If the iteration diverges or fails to meet tolerances, Abaqus may cut back the increment and retry. Automatic incrementation is usually preferred because it responds to nonlinear changes that are difficult to predict before the run. The guide also separates force residual convergence, correction-size checks, commonly used control parameters, automatic stabilization for unstable static problems, and transient time-integration accuracy checks. ## Why It Matters Nonlinear failure is often not a material or element problem alone. It can reflect step size, stabilization, contact status, load amplitude, solver controls, or transient accuracy. This page is the operational counterpart to [[Nonlinear Finite Element Analysis]]. ## Connections - [[Static Equilibrium Equation Solvers]] supplies the linear solves inside Newton iterations. - [[Direct Time Integration Methods]] supplies the transient integration context for dynamic steps. - [[Abaqus Resource and Parallel Execution]] affects the cost of repeated tangent solves and cutbacks. ## Sources - [[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]]