von Mises yield criterion

About: von Mises yield criterion is a research topic. Over the lifetime, 4374 publications have been published within this topic receiving 82642 citations. The topic is also known as: Von Mises stress.

Analysis of thermally induced stress and strain in continuous fiber-reinforced composites

Abstract: An axisymmetric model for the thermally induced stresses and strains in a deformable matrix continuous fiber-reinforced composite is developed. The model allows for a temperature- and strain-dependent matrix flow stress and is numerically implemented using a von Mises flow law. The model implementation permits the study of an arbitrary number of temperature cycles. This model is compared to a simple one-dimensional model that has been used in several pre-vious analyses. The models show good qualitative agreement, but there are important differ-ences, and the magnitude of the discrepancy depends sensitively on the properties of the composite. These models can be applied in analyzing experimentally measured strainvs tem-perature hysteresis loops to reveal thein situ mechanical properties of the deformable matrix. The models can also be applied to the design of continuous fiber-reinforced composites that will not suffer thermally induced cyclic-plastic deformation.

Stress analysis of a maxillary central incisor restored with different posts.

Abstract: Objectives: To evaluate the effects of different post materials on the stress distribution in an endodontically treated maxillary incisor. Materials and Methods: A pseudo 3-dimensional finite element model was created in a labiolingual cross-sectional view of a maxillary central incisor and modified according to five posts with different physical properties consisting stainless steel, titanium, gold alloy, glass fiber (Snowpost), and carbon fiber (Composipost). A 200 N force was then applied from two different directions; a) vertical load on the incisal edge, b) 45 degree diagonal load above the cingulum location. Stress distribution and values were then calculated by considering the pseudo three dimensional von Mises stress criteria. Results: Under two loading conditions, post made of steel showed greatest stress concentration at the post/dentin interface followed by titanium, gold alloy, Snowpost and Composipost. However, Composipost, which elastic modulus was closer to the dentin, produced highest stress values at 1/3 cervical area. Conclusions: Within the limitation of this simulated mechanical analysis, we can conclude that the physical characteristics of posts were important on stress distributions in post and core applications. Glass fiber post revealed more balanced stress distribution under functional forces. (Eur J Dent 2007;2:67-71)

Flow of viscoplastic fluids on an inclined plane: evaluation of yield stress

Abstract: Within the general category of so called generalized Newtonian fluids, there exists a class of materials which do not deform until the applied shear stress exceeds a critical value called yield stress Conversely, such a material behaves like a solid as long as the shear stress is less than the yield stress This class of materials is called viscoplastic fluids The question whether the true yield stress exists or not is indeed far from settled (1), but the notion of a yield stress has proved to be quite useful in practice in describing the steady shear rheological behaviour of a range of materials especially of particulate suspensions Consequently, yield stress appears as a parameter in all constitutive relations (which purport to describe the steady shear behaviour of viscoplastic materials), and its evaluation is important before an engineering flow problem can be solved Conversely, there are some simple hydrodynamic situations which allow the value of the yield stress to be extracted from macroscopi