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In purely structural analyses, deformation is the DOF, so materials that are dependent on strain (or deformation) trigger a nonlinear solution. Temperature-dependent coefficient of thermal expansion (CTE) or temperature-dependent elastic modulus do not cause a nonlinear structural solution, as temperature is a known input. (While CTE may be a nonlinear function of temperature, for example, it is still considered a ‘linear’ material insofar as structural analyses are concerned, as CTE is not a function of deformation or of strain.) These materials are also not path-dependent, so the timestep size will not affect solution accuracy. If temperature-dependent plasticity or creep is present, the accuracy will be dictated by the timestep size because these materials are path-dependent, whether or not they are temperature-dependent. In a heat transfer analysis, temperature-dependent materials will always trigger a nonlinear solution because, in thermal analyses, temperature is the DOF. Therefore, any materials dependent upon temperature will require Newton-Raphson method in heat transfer analyses.