I have completed my bachelor’s degree in aerospace in Amrita Vishwa Vidyapeetham University Coimbatore. I did my master’s degree in aerospace in IIT Kanpur, and the master’s thesis was related to Development and micro-mechanical analysis of prepreg based dis-continuous composites. I have involved in the development of a Representative Volume Element (RVE) and stiffness predictions using micromechanical method for prepreg based discontinuous composites (PBDC), the analysis helps in obtaining the variation of properties with respect to aspect ratio and volume fraction of the inclusion. In experimental work modification of prepreg machine have been conducted to improve the quality of the material My Ph.D. thesis topic is on Multiple localization and fracture in printed metallic rings and plates subjected to dynamic expansion. My work is divided into Analytical, computational, and experimental part. In the Analytical part of my work, I have studied the necking formability of anisotropic and tension-compression asymmetric of metallic sheets subjected to in-plane loading paths ranging from plane strain tension to near equiaxial tension. we have used three different approaches: a linear stability analysis, a nonlinear two-zone model and unit-cell finite element calculations. In the computational part I have created plate consisting of surface roughness and voids which are randomly distributed. I have studied the necking behaviour of the model by using ABAQUS and Hyper mesh for meshing. In the experimental part of the thesis, I have conducted ring expansion test on ring specimen in University of Texas Austin.