Contents of Part I

Introduction............................................................................................................. 5

Part I. Stretching........................................................................................ 8

Chapter 1. Theory of finite element method for solution of elastic tasks

                   at modeling of forming......................................................................... 8

1.1. Scheme of calculation by finite element method................................................. 8

1.2. Basic equations of finite element method at solution of elastic tasks................... 9

1.3. Numerical solution of elastic task for processing a flat ring blank..................... 15

Chapter 2. Theory of finite element method for solution

                    of elastic-plastic tasks at modeling of forming................................ 26

2.1. Basic equations of finite element method at solution

       of elastic-plastic tasks.................................................................................... 26

2.2. Numerical solution of elastic-plastic task for processing

       a flat ring blank.............................................................................................. 42

2.3. Numerical solution of elastic-plastic task for processing

       a plate or a sheet........................................................................................... 44

Chapter 3. Brief theory of stretching................................................................... 47

3.1. Analytical solution of elastic task.................................................................... 47

3.2. Analytical solution of plastic task.................................................................... 50

Chapter 4. Modeling in system Marc of specimen tensile and

                   straightening a sheet by stretching................................................... 55

4.1. Creation of folder and file of project............................................................... 55

4.2. Formulation of the problem in three-dimensional space................................... 56

4.3. Designing the calculated scheme of tensile of blank in the form

       of specimen or sheet...................................................................................... 63

4.4. MESH GENERATION of finite elements on blank........................................ 68

4.5. BOUNDARY CONDITIONS for DISPLACEMENT and

       GRAVITY LOAD in nodes of mesh of finite elements.................................... 73

4.6. The build of stroke plot of machine clamp for tensile of blank.......................... 78

4.7. Determination of CONTACT of clamps with blank and stroke of clamp......... 83

4.8. MATERIAL PROPERTIES and MASS DENSITY of blank......................... 91

4.9. Approximation of dependence of intensity of stresses from intensity

       of deformations in account of hardening the blank........................................... 92

4.10. Loading the dependence of intensity of stresses from intensity

         of deformations of blank.............................................................................. 98

4.11. Determination of LOADCASES and JOBS............................................... 102

4.12. A choice of target data after running the project.......................................... 107

4.13. Start of project on RUN of modeling the forming........................................ 109

4.14. Animation of stretching the blank................................................................ 113

4.15. Stressed state of blank and dynamics of transition

        of finite elements in plastic state................................................................... 117

4.16. Criteria of fracture of blank on the basis of stresses and deformations......... 124

4.17. Analysis of danger of blank fracture on the basis of stresses

        and determination of rational parameters of forming..................................... 126

4.18. Deformed state of blank............................................................................ 128

4.19. Analysis of danger of blank fracture on the basis of deformations

        and determination of rational parameters of forming..................................... 134

4.20. Diagrams of forces during the stretching..................................................... 135

4.21. Conclusion................................................................................................ 139

Description of contents of compact disk and scheme of use............................ 141

Literature............................................................................................................ 142