Adaptive material properties tailoring for stress concentration

Avoiding stress concentrations is essential to prevent engineering failures. Advanced manufacturing methods like multi-material additive manufacturing are enabling the realization of structures with intricate spatially varying mechanical properties, offering an attractive pathway for redistributing the stress by adjusting mechanical properties in selected locations. This work effectively marries the concepts of material properties and stress distribution, and addresses the issue of what material properties minimize stress concentration by adaptive design of Young’s modulus, Poisson’s ratio, shear modulus and yield strength for both isotropic and anisotropic materials. Regions of adjustable material properties are created around areas of high stress to alter the stress distribution. The accurate mechanical properties distributions are calculated using adaptive design method in a finite element analysis framework. The effectiveness of the much-enhanced material properties on reducing stress concentrations is demonstrated for thin plate with circular hole and L-shaped thin plate. Results show that the peak stress can be reduced by up to about 70 % in isotropic designs and up to over 80 % in anisotropic designs.