Mechanical properties of Auxetic 316L stainless steel sheets for orthopedic applications

The current research trend focuses on the development of many superior, high-tech and cost effective materials from conventional materials to enhance their potential in various fields of engineering and biomedical. Under the smart materials era, almost in the last ten decades, the materials turned into multifunctional. More than three decades there has been overarching focus on study of auxetic materials which comes under the 16 smart materials of 21st century. They have already made a significant impact on engineering, biomedical, aerospace and many other industries. However, they required further optimization of different characterization and properties to exploit their benefits to biomedical and other fields. Therefore, the main focus of present thesis is to design, fabricate, characterize and interpret the mechanical and functional performances to develop a novel auxetic metal plate. For this purpose stainless steel 316L sheet with auxetic hexagonal (re-entrant) geomertical pattern considering dimensionality, flexibility and deformation mechanism are produced. Multidisciplinary approach with high precision, economic and environment friendly high-tech macro techniques is adopted in the manufacturing and characterization of purposed auxetic plate. The experimental setup for mechanical characterization in vitro environment is targeted throughout this research study. The results achieved in this thesis could be applicable in biomedical field particularly orthopaedic applications where tailored mechanical properties such as tensile strength and bending are required according to real life configuration such as internal fixtators (supporting plates) for the fixation of fractured bone. To our knowledge research study on 316L stainless steel auxetic plates at macro scale for orthopedic applications does not exist in literature. Keywords: Re-entrant structure, Auxetic effect, Tensile strength, three-point bending, deformation mechanism.