Devolopment of microstructure damage in structurally heterogeneous materials under deformation

Abstract

The proposed model represents a micro-heterogeneous medium with random properties of elastic-brittle microstructure elements and with fractures forming during the deformation of structurally heterogeneous materials. The probability of stress exceeding the ultimate strength in one element determines the probability of the failure of this element and the relative damage at the micro level. The suggested methodology for the calculation of damage is based on the use of a single parameter, specifically, the distribution density of the ultimate strengths of structural elements. Defining the increment step for the macro strain axis, we draw segments of the stress-strain curve taking into account the changed properties on each interval. The influence of damage on the stress-strain curve is observed. Uniaxial stress-strain diagram calculation for the exponential distribution of ultimate microstructure strengths in a model material is studied using the proposed methodology. Keywords

Analysis of the Multi-Directional Forging of Aluminium Alloy 7075 Process Parameters: Numerical and Experimental Analysis

“…The new structures had new lattice interaction at the dislocations and at the grain boundaries increasing grain refinement. However, this new structure prevents boundary migration and the dynamic recovery of the structures, resulting in more lattice rearrangement of the dislocations and damages [41].…”

“…The Taylor's concept explains why the surface hardness result was low. The high strains decreased the dislocation density, at the high temperature lowering the plastic resistance of grains and hardness [41,47,48].…”