Crack tip fields and fracture resistance parameters based on strain gradient plasticity

• Influence of plastic material properties on fracture resistance parameter is analyzed. Mechanism-based strain-gradient plasticity theory, Taylor dislocation model are used. Amplitude and stress intensity factors for strain gradient formulated. Behavior SIFs differs significantly from HRR solution. The crack tip mechanics solids investigated analytically numerically. A first-order mechanism-based (MSG) theory based Taylor’s adopted implemented in the commercial finite element package ANSYS by means a user subroutine. Two boundary value problems considered, single edge tension specimen biaxially loaded plate. First, fields characterized. Strain effects associated with hardening mechanisms elevate stresses relative to conventional plasticity. parametric study conducted differences predictions quantified. Moreover, asymptotic nature solution investigated. numerical results reveal that singularity order predicted MSG equal or higher linear elastic solids. Also, field appears not have separable contrarily what has been shown version plasticity, exhibits sensitivity properties. Secondly, analytical approaches employed formulate novel amplitude generalized J -integral derived used characterize nonlinear factor. closed-form equation factor obtained. also decomposing field. Nonlinear solutions determined across wide range values length scale l exponent N . domains relevance identified, setting basis application damage assessment.