Due to the heterogeneous nature of composite materials, residual stresses build up during manufacture of composite products. Such stresses can change the final shape of a component from the tool shape. Temperature induced stresses and deformations of thick cylindrical parts have been studied by a number of researchers using analytical approaches. However these approaches cannot solve a thick composite component with arbitrary geometry. Finite-element-method (FEM) analysis was conducted in this study using ABAQUS. Mechanical and thermal properties of composite materials were determined through microstructure analysis. Different element types were compared with respect to their prediction accuracy. The technique of application of FEM is discussed in the paper. Spring-in values of 90° angles with varying curvature at the corner are predicted. Reasonably good agreement between the prediction and the measurement is achieved.
A method for identifying the physical parameters of joints in mechanical systems is presented. In the method, a multi-d.o.f. (degree-of-freedom) system is transformed into several single d.o.f. systems using selected eigenvectors. With the result from modal testing, each single d.o.f. system is used to solve for a pair of unknown physical parameters. For complicated cases where the exact eigenvector cannot be obtained, it will be proven that a particular physical parameter has a stationary value in the neighborhood of an eigenvector. Therefore, a good approximation for a joint physical parameter can be obtained by using an approximate eigenvector and the exact value for the joint parameters can be reached by carrying out this process in an iterative way.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.