Fiber orientation optimization for mitigating stress concentration factors in perforated composite leaf-springs

Resumo

Advances in composite materials are enabling the replacement of traditional steel leaves in heavy duty vehicle suspension springs with composite ones. By means of analytical simulations written in Python and grounded in classical lamination theory, this study evaluates spring leaves at three fiber volume fractions (Vf = 50 %, 60 %, 70 %) composed of epoxy resin and basalt fiber, showing how systematic variation of fiber orientation and Vf governs axial stiffness, in plane and out of plane moduli, anisotropy ratios, transverse Poisson’s ratio, and stress concentration factors around the central circular discontinuity. Results indicate that optimizing Vf from 70 % down to 60% does not significantly alter stiffness while preserving reduced stress amplification within specific orientation windows, thereby providing practical guidelines for designing lighter high performance suspension components, highlighting the Topology optimization role in such designs.