Papers by Keyword: Plastic Modulus

Abstract: Newton-Raphson method is used in global equilibrium for the numerical solution of elasto-plastic problems. It is necessary to determine the fourth-rank constitutive parameters of consistent tangent modulus in each integration point. Euler backward method and implicit stress integration is applied while constitutive model is implemented into ANSYS software. Take Chen, Jiao, and Kim model (2005) as an example, comparison of fourth-rank constitutive parameters and without fourth-rank constitutive parameters of consistent tangent modulus indicates that the convergence is obviously influenced by fourth-rank constitutive parameters of consistent tangent modulus for the larger load case, whereas the influence of plastic modulus is almost neglected.

Abstract: Complex hierarchical assembly and presence of large amount of organics and water content are responsible for enough amount of plasticity in bone material. Plastic properties are not only important to assess the various changes and fracture risk in bone but also for the development of better bone implants and joint replacements. The present study is focused on the post-yield behavior of cortical bone. The plastic properties of goat femoral and tibiae cortical bone were assessed and compared in terms of plastic modulus (H), tangent modulus (Et), plastic work (Wp) and plastic strain (εp) using uniaxial tensile test. Both femoral and tibiae cortical bone were found to be having similar post-yield behavior and significant stiffness loss was observed in both the bones during plastic deformation. The value of plastic modulus for femoral cortical bone was found to be 1.2 times higher as compared to the corresponding value for tibiae cortical bone. This shows higher hardening rate for femoral cortical bone. It was also observed that femoral bone requires higher energy during plastic deformation until fracture as compared to tibiae cortical bone.

Abstract: The paper investigates the mechanical properties of sintered hollow sphere struc- tures. First of all, the Young's modulus, plastic modulus, initial flow stress, initial flow strain, plateau stress and densifcation strain are derived from compressive tests. In addition, the material behaviour during the compressive testing is described. Furthermore, the influence of different specimen shapes on the results is discussed.