The elaborated system will enable description of the critical phenomena leading to failure in sheet metal forming as well as creating a valuable tool, in the form of computer procedure for FEA, for engineers involved in process design. To date such programs are not available. The systems will provide design engineers with analytical tools for testing design at the computer terminal so that the expensive trail and error process with real tools may be reduced or climinated
The aim of the work is development of a modern sheet metal forming process design technique and diagnostic system. The proposed method is based on the incorporation of Forming Limit Diagrams (FLD), Wrinkling Stress Diagrams (WSD) and Constitutive Equations (CE) good describing the materials reaction on the complex deformation conditions into Finite Element Analysis (FEA) programme.
For determination of the limit strain instead of FLD the concept of the Forming Limit Stress Diagrams (FLSD) will be used. The diagrams independent of the deformation history are more intrinsic than the classical (FLDs), which are strongly dependent on the former pre-strain of the sheet. FLDs will be analytically calculated by using modern theories base on the development M.K. theory as well as will be determined experimentally to conform theoretical predictions for new generation of materials used mainly for car body production. For determination of wrinkling the wrinkling stress diagram will be elaborated.
Finite element analysis will use a state of the art computer package (probably MARC and ABAQUS), which enables the simulation of the sophisticated material models and complex boundary conditions. The material models and friction conditions will be established by a proper set of the experiments. The procedure will involve tests for evaluating strain hardening and strain softening, friction trails, plastic anisotropy as well as wrinkling.
The programming part of the project will consist of writing a procedure which could be linked to the above mentioned existing FEA programs.
Funding SchemeCSC - Cost-sharing contracts
4465 Leça Do Balio